Output references and failure navigation: open file:line, copy paths/URLs/hashes, jump between failures #353

Goal

Turn reliable references in command-owned output into user-initiated actions, and make failures easy to revisit. Extend the existing command-block Actions, /open, /find, /filter and editor bridges, rather than adding a permanent overlay or building a second debugger.

Actionable references

Conservatively recognize high-confidence:

• Source locations such as src/main.ts:42 / absolute file paths (file/line/column when unambiguous).
• URLs, Git commit IDs, test failure locations, and device identifiers (e.g. Android serials) when the source format is reliable.
• Other typed references only when supported by a real handler and explicit user demand.

From a selected owning command block, offer context-appropriate actions: Copy value; Open file at line; Reveal/open URL via supported host actions; Inspect Git commit; Stage a device-specific follow-up command for review. No executable action based on output without confirmation. Never change the shell's current command or execute automatically.

Failure navigation

• Use nonzero exit and interruption as authoritative lifecycle states.
• Parse familiar build/test diagnostics only as hints; a string containing “error” does not establish command failure.
• Jump by stable command ID (not visual row), navigate previous/next relevant result, open source, copy failure with surrounding context, Compare (Compare output: diff two executions of a command #352/Compare output: diff two runs of a command #361), Copy as Report (Copy as Report: Markdown/plain diagnostic reports from command blocks, with review and optional redaction #351/Copy as Report: reviewed Markdown/plain reports from command blocks #360).
• Do not render distracting permanent underlines/buttons over all program output; keep actions discoverable in owned Action menus/selection and keyboard controls.
• Handle malformed paths, escapes/OSC, hostile URLs, symlinks, relative cwd, legacy/restored/truncated output and missing editors honestly.

Defaults

Recognition should be lazy/contextual, local and non-executing. Do not add an automatic error panel, ongoing output scanning or mandatory integrations. Selected actions never transmit information without an explicit user instruction.

Acceptance

• Resolve reference provenance against the correct command and cwd; handle path:line and URLs safely.
• Keyboard-first actionable reference picker or menu, with accurate unavailable reasons.
• Failure navigation reuses existing transcript navigation and exact command records.
• No action steals input ownership from foreground/managed programs.
• Real-PTY, narrow/NO_COLOR/Safe, hostile-output and restored-transcript tests.
• Document what is deterministic and what is heuristic, with no claims of unsupported actions.

Parent: #359. Blocks/copy foundation: #358. Report/Compare: #360/#361.