feat(terminal): open file paths on Cmd/Ctrl+click

[dancras]

Cmd/Ctrl+click a file path printed in a terminal to open it in the editor. Agents reference files (src/foo.ts:42); this makes those references jump straight to the file instead of requiring a manual search.

The flow

1. An agent (or any TUI) prints a file path in a terminal pane.
2. Hold Cmd/Ctrl: file paths underline like URLs.
3. Click: the file opens in the editor preview, jumping to :line:col when present.
4. If the path matches more than one file in the project, a small picker lists the candidates.

pathclick-demo.mp4

Design notes

• Capture-phase opener. Reuses the existing GH Bug: Title: Links do not open in browser with click or Cmd+Click on macOS #58 gesture handling, so it works even when an agent TUI has xterm mouse reporting on.
• Segment-boundary suffix match against the project's file list: one match opens directly, zero or many show the picker.
• Custom link provider for the hover underline. WebLinksAddon can't be reused, its new URL() gate silently drops scheme-less paths. Third party option xterm-link-provider rejected to avoid unjustified dependency.
• Scoped to agent panes; the scratch shell keeps plain URL behavior.

Testing

Unit tests for path parsing and suffix matching. make check-all clean.

Also have an uncommitted e2e test script and demo recording script.

[simion]

Nothing blocking, nits only. None of these gate a merge.

• Wrap-boundary off-by-one in the provider: a token ending exactly at a soft wrap makes toPos(end) advance to the next row at offset 0, so the range ends at x: 0 in xterm's 1-based coordinates. Clamp to the previous row's last cell.
• AuxTerminal still arms on path targets: onDown swallows the gesture, then the aux callback drops it, so Cmd+click on path-like text in the scratch shell eats the click and does nothing (including for a TUI with mouse reporting that wanted it). Either a URLs-only mode that skips arming, or support path-open there too, AuxTerminal has taskId.
• handlePathTarget's .catch(() => {}) swallows a failed file-list fetch: the click does nothing with no explanation. A toast matches how the Git panel reports IPC failures.
• Nit: "and/or" and bare domains ("termic.dev") match the token regex, so they hover-underline and click through to a "No matches" picker. Fine for v1.
• Nit: after the picker closes, focus lands on the invisible anchor (not focusable), so the terminal drops focus. Refocus the terminal in onPick/onClose.

Checked the integration: openPreviewTab/revealAt and the task-relative path form match the store and EditorPane, so single-match opens and line jumps work as written. The capture opener swallows the whole gesture, so the provider's activate can't double-fire; the WebLinksAddon new URL() rationale is accurate.

[dancras]

Resolved 1,2,3 and 5 and also found some extra edge cases regarding regexes in the follow up review.

Some common formats (domains, emails) are technically valid paths so for simplicity I've just left them matching. Worst case UX is a "No matches" popup.

[simion]

Merged. No follow-up needed.

The key insight (splitting linkAt into url|junk|path and folding the scan into one regex) is exactly right — it kills the class of bug where a URL fragment leaks through as a bogus path. The {1,255} segment bound is the real win: caught the O(n²) hover-underline stall before it shipped, and there's a 40k-char blob timing test guarding it. 20/20 tests pass, tsc clean.

Checked the two things I'd worry about:

• urlsOnly on the scratch shell → path tokens no longer arm the opener in AuxTerminal, so no swallowed clicks under a mouse-reporting TUI. Confirmed.
• picker focus → onCloseAutoFocus routes to termRef on dismiss, leaves it for the editor on pick.

One cosmetic note: Windows C:/ drive paths get eaten by the scp-remote branch — don't care, this is a Mac app. Bare domains/emails still underline and resolve to nothing, already called out. Fine tradeoff.

Thanks, nice work.