feat: Grep and Glob results render as clickable locations

[oratis]

What

The fourth render intent from the DSH adoption plan (§1.6), specified there and deferred by #271: Grep/Glob cards in the desktop rendered as a grey text blob; now they render as a list of openable file locations — line number and matched text included in content mode — each row wired to the same file-panel opener the card header already uses.

Why parsing the result text was the wrong design (and what this does instead)

The deferral reason was real: re-deriving entries from the formatted result text means parsing path:line:text, whose : separator is ambiguous the moment a path contains one. Grep itself dodges that ambiguity internally with ripgrep's --null output — throwing the exact rows away and re-parsing the lossy format back would be guesswork presented as UI.

So the entries are attached at the source: both tools publish the rows they already hold as ToolResult.data.locations ({path, display?, line?, preview?}, absolute path for opening, printed form for display, capped at MAX_TOOL_LOCATIONS = 200). The render intent stays a pure function of the call's arguments; the entries ride the result's existing structured-data channel, which the app-server has always serialized verbatim — ToolCompletedEvent.result now declares data? instead of narrowing it away, documenting the wire rather than widening it.

Clients share one validating extractor, readToolLocations, so a malformed payload degrades to "no locations" everywhere instead of crashing one renderer.

Honest boundaries

• Replay degrades, by design. A session restored from its log has only the text the model saw (ToolResultBlock.content), so replayed cards fall back to today's plain-text body — same characters, no buttons. Persisting presentation data into thread items is a possible follow-up; it was left out to keep the stored formats untouched.
• Withheld stays withheld. Locations are built from the post-contract-filter rows; a test pins that a denied path never leaks through the structured channel.
• Grep's head_limit now slices rows before formatting so entries line up with shown lines — the emitted text is unchanged byte for byte.

Verification

• typecheck · lint · format:check · build · docs:check all green.
• core 1181 passed (rg-backed Grep tests run for real via a local ripgrep, DC_REQUIRE_RIPGREP=1) · desktop 105 passed.
• Vite preview harness (preview-toolcards.html), checked in the in-app browser: line-numbered Grep rows with match previews, Glob's relative rows, clicks reporting the absolute path, and a restored-session card (result text, no data) falling back to plain text.

🤖 Generated with Claude Code