docs: correct Go version and remove unshipped SFTP browser claims

- README: build-from-source requires Go 1.25+ (matches go.mod), was 1.23+.
- docs/v2-report.md: the in-app SFTP file browser was never built (no `t`
  action, no xfer/sshx/browser packages, pkg/sftp not a dependency). Cut the
  false "shipped" claims and moved it into the Deferred section.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

README.md

@@ -106,7 +106,7 @@ that ships in `%WINDIR%\System32\OpenSSH`.
 
 ### Build from source instead
 
-Requires Go 1.23+.
+Requires Go 1.25+.
 
 ```sh
 make install     # builds and installs into $GOBIN (or $GOPATH/bin, ~/go/bin)

dist/SHA256SUMS

@@ -0,0 +1,5 @@
+c5fc3eb4c3903aa2b7a30aba13e3646b960b020da6b49ca99ae9e63e2de431ce  dial-darwin-amd64
+708b4037e7aa857b7311f9d707ebfb197d4fb3018a55ba0c885df96c8268e567  dial-darwin-arm64
+05e27c52bd21d525f78b5b43bc14ee1a7c3b2b5629165eec104028731f45211b  dial-linux-amd64
+94a89c8de21f1a4673f82ab4f230346839b9bd8408e9599eac566c2cba689a3f  dial-linux-arm64
+cd5786b303799cc001215afd793c26883c77eb04e10a161dd467909595aa9b09  dial-windows-amd64.exe

docs/v2-report.md

@@ -11,10 +11,10 @@ added and where it stands.)
 interactive host picker: it reads `~/.ssh/config`, shows a clean, static,
 high-contrast, low-light-friendly list, and on selection `exec`s the real system
 `ssh` client into the host (so tty/ProxyJump/agent forwarding just work). It's a
-single Go binary. v2 added sorting/grouping, an SSH key generator, and an in-app
-SFTP file browser. Optional features include a YubiKey launch gate. App data
-(recents, favourites, settings) lives under `~/.ssh/.dial/` so it syncs via the
-user's existing Syncthing.
+single Go binary. v2 added richer sorting/grouping and a native SSH key
+generator. Optional features include a YubiKey launch gate. App data (recents,
+favourites, settings) lives under `~/.ssh/.dial/` so it syncs via the user's
+existing Syncthing.
 
 ## What v2 shipped
 
@@ -40,21 +40,6 @@ user's existing Syncthing.
    duplicate an existing alias. It's a rebuild of an old `create_ssh_keypair.sh`,
    fixing that script's macOS-only `sed`, key-deletion, and unquoted-append bugs.
 
-5. **In-app SFTP file browser.** Pressing `t` on a host opens a dual-pane
-   browser (local left, remote right) that transfers files without leaving dial:
-   - Side-by-side panes, `tab` to switch, arrow/`jk` to move, `enter` to descend,
-     `backspace` up, `space` to batch-select.
-   - Directional transfers: `→`/`p` push local→remote, `←`/`g` pull remote→local,
-     into the other pane's current directory.
-   - Recursive directory transfers, aggregate progress bar, and overwrite prompts
-     (`[o]verwrite`/`[s]kip`/`[r]ename`, uppercase = apply to all remaining).
-   - **Same-session resume**: an interrupted transfer retried in the same session
-     resumes partial files instead of restarting.
-   - Connects over SFTP in-process (`pkg/sftp` + `golang.org/x/crypto/ssh`),
-     reusing the host's real `~/.ssh/config` (resolved via `ssh -G`), including
-     ProxyJump, authenticating via ssh-agent or unencrypted key files.
-   - When the YubiKey gate is enabled it re-challenges before opening the browser.
-
 ## Architecture (packages)
 
 Existing v1 packages: `sshconf` (read-only config parser), `store`
@@ -63,87 +48,50 @@ Existing v1 packages: `sshconf` (read-only config parser), `store`
 
 - `internal/keygen` — native key generation (crypto + `x/crypto/ssh`), key-file
   writing with correct perms, and safe `~/.ssh/config` appends.
-- `internal/xfer` — the transfer engine. A small `fs` abstraction lets push and
-  pull share one recursive copy routine; handles progress, conflict policy, and
-  resume. **Fully unit-tested against an in-memory SFTP server** (no sshd needed).
-- `internal/sshx` — the connection layer. Resolves effective config via
-  `ssh -G <alias>`, builds the `ssh.ClientConfig` (agent + key auth, known_hosts
-  verification), and dials directly or through a ProxyJump chain.
-- `internal/browser` — the dual-pane Bubble Tea file browser, using `xfer` for
-  transfers and coordinating the overwrite prompt across goroutines.
 
-The picker's `t` key returns an `ActionSFTP` result; `main` then (re-)runs the
-gate, connects via `sshx`, opens an `sftp.Client`, and runs the browser. The
-default flow is now a loop: pick → connect (exec, ends) or sftp (returns to the
-picker). Host *selection* stayed decoupled from the *action*, which is what let
-SFTP reuse the picker cleanly.
+Host *selection* stayed decoupled from the *action*, which keeps room to add new
+per-host actions (e.g. the deferred SFTP browser) without disturbing the picker.
 
 ## Current state
 
 - **Complete and green.** All packages build; `go vet` clean; unit tests pass
-  for `sshconf`, `store`, `yubikey`, `picker`, `keygen`, `xfer`, `sshx`.
+  for `sshconf`, `store`, `yubikey`, `picker`, `keygen`.
 - **Cross-compiles** to all five targets (macOS arm64/amd64, Linux amd64/arm64,
-  Windows amd64). Binary grew from ~3.5 MB to ~6.1 MB — the cost of the
-  in-process SFTP stack (`x/crypto/ssh` + `pkg/sftp`), a deliberate trade chosen
-  over shelling out to the system `sftp`.
-- **Live-verified via tmux** (against an in-memory SFTP server): dual-pane
-  render, navigation, batch selection, single-file push, recursive directory
-  push (contents verified on the far side), and the overwrite-conflict prompt
-  (goroutine↔UI coordination). keygen verified end-to-end (valid ed25519,
-  correct perms, config append with backup).
+  Windows amd64).
+- **Live-verified via tmux**: keygen verified end-to-end (valid ed25519, correct
+  perms, config append with backup); picker navigation, sort cycling, tag
+  grouping, and favourites toggling all exercised.
 
 ## Known limitations / not yet exercised
 
-- **The SFTP connection layer is now live-verified against a real sshd.**
-  Against a test host (key-based auth, no agent, unencrypted key loaded directly
-  from `IdentityFile`): `sshx.Connect` + SFTP listing, an SFTP write/read/remove
-  round-trip, and a full-TUI pull *and* push both passed with byte-for-byte
-  sha256 matches. An env-gated live test (`DIAL_LIVE_HOST=<host> go test
-  ./internal/sshx -run TestLiveConnect`) is kept for re-running this. Still
-  unverified against a real host: **ProxyJump chaining** and **agent-backed /
-  encrypted-key auth** (the test host used a plain key file, no agent). (Same
-  hardware-untested posture remains for the YubiKey gate.)
-- **ssh-agent on Windows** uses named pipes, not the `SSH_AUTH_SOCK` unix socket
-  the code dials; it compiles, but agent auth on Windows likely needs follow-up.
-- **Encrypted key files** are skipped by the SFTP auth (it relies on the agent
-  for those) — dial never prompts for a key passphrase when connecting.
-- **No mid-transfer cancel** — resume covers interruptions, but there's no
-  in-flight cancel key; a stuck transfer would need Ctrl-C out of the browser.
-- **known_hosts is verify-only** — an unknown host errors out ("ssh to it once
-  first") rather than offering trust-on-first-use; no known_hosts management.
+- **YubiKey gate is hardware-untested** — the challenge-response and recovery-code
+  logic have unit coverage, but the gate has not been exercised against a
+  physical YubiKey + `ykman` on real hardware.
 - Still unsigned binaries (Gatekeeper/SmartScreen warnings); no CI/releases.
 
 ## Deferred (explicitly out of this pass)
 
-Idle-timeout gate option; crash-persistent resume (surviving a dial restart);
-distribution/signing/package managers; multi-select/batch actions *across hosts*
-(distinct from the in-browser batch file selection, which shipped); per-host
-notes; fuzzy search.
+- **In-app SFTP file browser.** Planned for v2 (see `dial-v2-plan.md` §3) — a
+  dual-pane push/pull browser opened with `t`, built on an in-process SFTP stack
+  (`pkg/sftp` + `golang.org/x/crypto/ssh`). **Not built.** No `t` action, no
+  transfer/connection packages, and `pkg/sftp` is not a dependency. This is the
+  largest deferred item and would be the natural centrepiece of a v3.
+- Idle-timeout gate option; distribution/signing/package managers; multi-select
+  actions across hosts; per-host notes; fuzzy search.
 
 ## Open questions & directions to brainstorm
 
-1. **Real-host validation plan for SFTP** — what's the cheapest way to smoke-test
-   the connection layer (a throwaway VM? a container running sshd? a known host)?
-2. **Windows agent support** — is Windows a real target for the SFTP browser, or
-   is it macOS/Linux-first? Determines whether named-pipe agent support is worth
-   building.
-3. **Cancel & crash-persistent resume** — how often do transfers of very large
-   files over flaky links actually happen? That's the trigger for investing in
-   disk-persisted transfer state.
-4. **known_hosts UX** — is verify-only acceptable, or should the browser offer to
-   record a new host key (with a clear prompt)?
-5. **Grouping refinements** — should multi-tagged hosts optionally appear under
+1. **SFTP browser — build it next?** It was the headline v2 plan but slipped.
+   Worth scoping as the v3 centrepiece, and if so, what's the cheapest way to
+   smoke-test the connection layer against a real sshd (a throwaway VM? a
+   container running sshd? a known host)?
+2. **Grouping refinements** — should multi-tagged hosts optionally appear under
    *every* tag? Should there be a per-tag filter shortcut or colour legend?
-6. **Distribution** — Homebrew tap / Scoop / `install.sh` / signed releases via
+3. **Distribution** — Homebrew tap / Scoop / `install.sh` / signed releases via
    CI: worth doing now that the feature set is broad?
-7. **SFTP polish** — a file preview? delete/rename/mkdir on either side? a "sync
-   this directory" one-shot? These edge toward a full file manager — where's the
-   line for a tool that's fundamentally a host picker?
 
 ## How to build / try
 
-- Build: `make build` (native) or `make dist` (all platforms). Requires Go 1.23+.
+- Build: `make build` (native) or `make dist` (all platforms). Requires Go 1.25+.
 - Keys: `dial keygen` (no external deps).
-- SFTP browser: `dial`, pick a host, press `t` (needs the host in known_hosts and
-  agent/key auth working — i.e. a host you can already `ssh` to).
 - YubiKey gate: `dial yubikey enable` (requires Yubico's `ykman`).