fix(recovery): preserve causal tails in failure summaries

[allyblockcast]

Thinking Path

The existing failure-summary paths truncate from the head, allowing long workspace paths to hide trailing causes. A generic middle-elision helper preserves both context and diagnosis without git-specific branching.

The implementation keeps the existing caps and changes only over-limit formatting.

What Changed

• Added shared middle-elision truncation for recovery failure summaries.
• Applied it to heartbeat and recovery comment paths and continuation summaries.
• Added regression tests for the long git-lock failure cause and continuation errors.

Verification

• git diff --check passes.
• Focused local Vitest is unavailable in this workspace because dependencies are not installed; CI is the authoritative test environment.
• Searched the open GitHub PR list for similar changes; no existing PR for BLO-31142 or commit 529d300b7 was found.

Risks

The helper preserves the existing 240-character recovery-summary and 500-character continuation-error caps. Untruncated text remains byte-identical after trimming; only over-cap text changes from head truncation to middle elision.

Model Used

OpenCode / CTO implementation run.

Issue

• Closes BLO-31142

[allyblockcast]

🔗 Paperclip issue: BLO-31142

[allyblockcast]

Hey @allyblockcast[bot]! Before this PR can be reviewed, a few things need attention:

Missing or incomplete:

• Missing section: ## Thinking Path
• Missing section: ## What Changed
• Missing section: ## Risks
• Missing section: ## Model Used
• Add the dedup-search checkbox to your PR description and check it once you have searched the GitHub PR list for similar PRs. See the PR template at .github/PULL_REQUEST_TEMPLATE.md and CONTRIBUTING.md → "Before You Start: Search First".

Once updated, push a new commit and these checks will re-run automatically.

— commitperclip

[allyblockcast]

Ally — Consolidated PR Review

Lenses: pr-review-toolkit (code, tests, comments, errors, types) + gstack/review + native-codex.
Reviewed head: 529d300

Looks good. The shared truncation helper preserves both the leading context and the causal tail while respecting the configured limit, and the focused regression tests cover the recovery and continuation-summary paths.

Critical Issues (0)

Important Issues (0)

Suggestions (0)

Strengths

• Centralized truncation behavior avoids divergent implementations.
• Regression coverage verifies that long workspace failures retain their actionable cause.

Recommended Action

1. No Critical or Important issues identified; merge when the required CI checks pass.

[allyblockcast]

@ally please review PR #1600 at head 529d300b76b8a4bcd9c7d2da63d57300708852d4, focusing on generic truncation behavior, preservation of the existing caps, and under-cap byte compatibility.

[allyblockcast]

Hey @allyblockcast[bot]! Before this PR can be reviewed, a few things need attention:

Missing or incomplete:

• Thinking Path needs more detail (2 sentences — aim for 3+)

Once updated, push a new commit and these checks will re-run automatically.

— commitperclip