feat(transcript): collapse dense tool runs

Harvested from PR #2738 by @idling11.

Co-authored-by: idling11 <8055620+idling11@users.noreply.github.com>

docs/V0_9_0_EXECUTION_MAP.md

@@ -48,6 +48,7 @@ harvest/stewardship commits:
 | #2733 PlanArtifact for Plan mode | Locally harvested as a broader continuity-artifact slice. | Added rich `update_plan` fields for objective, context, sources, files, constraints, verification, risks, and handoff notes; renders them in the transcript card and Plan confirmation prompt; preserves them through `/relay`, fork-state, and saved-session replay. `cargo test -p codewhale-tui --bin codewhale-tui --locked plan_ -- --nocapture`, `cargo test -p codewhale-tui --bin codewhale-tui --locked relay_slash_command_routes_to_session_relay_instruction -- --nocapture`, and `cargo clippy -p codewhale-tui --locked -- -D warnings` passed. |
 | #2736 sub-agent model inheritance | Locally harvested with explicit-override and provider-shaping tests. | Tool-agent routing now inherits the parent runtime model instead of hard-coding `deepseek-v4-flash`, while explicit DeepSeek-style tool-agent overrides still win. The `reasoning_effort = off` fast lane is covered by strict OpenAI-like provider request-shaping tests. Credit @h3c-hexin; comment/close the original after the integration branch is public. |
 | #2737 configured `skills_dir` discovery | Locally harvested with explicit-config precedence. | The system prompt now unions workspace-discovered skills and configured `skills_dir` skills instead of treating the configured directory as a fallback. Explicit configured skills are inserted before global defaults so they are not lost behind a large global skill library. Credit @h3c-hexin; comment/close the original after the integration branch is public. |
+| #2738 dense tool-call transcript collapse | Locally harvested with expansion, cache-key, and safety fixes. | Successful read/search/list-style tool runs collapse by default once they cross the density threshold; failures, running cells, shell/exec, patch/write/edit/delete, diff preview, plan update, and review cells stay visible. Users can expand a group with Enter/Space/mouse and can set `tool_collapse = "compact" | "expanded" | "calm"`. Credit @idling11 and issue #2692; comment/close the original after the integration branch is public. |
 | #2636 project-context mtime cache | Defer direct merge; harvest only after cache key/signature is widened. | Must include constitution changes, auto-generated context deletion, canonical path equivalence, and overwrite detection before landing. |
 | #2634 HarmonyOS port | Locally harvested with additional Nix-chain clearance; keep credited and do not close until the integration branch is public. | User-supplied MatePad Edge demo (`https://bilibili.com/video/av116689597368905`) confirms real-device interest. Added env-driven OpenHarmony SDK setup, OHOS platform guards/fallbacks, self-update disablement, and OHOS target gating for Starlark execpolicy parsing plus PTY support so published OHOS builds do not pull `nix` 0.28 through `rustyline` or `portable-pty`. `cargo check --workspace --all-features --locked`, focused PTY/clipboard tests, and `cargo tree --locked -p codewhale-tui --target aarch64-unknown-linux-ohos -i nix@0.28.0` passed; full OHOS target check is blocked on this host because `OHOS_NATIVE_SDK`/target CC/sysroot are not configured and `ring` cannot find `assert.h`. |
 | #2687 append-only mode/approval prompt | Defer direct merge; draft has compile failures and Plan-mode prompt correctness risks. | Any future harvest must keep stable `message[0]` genuinely mode-agnostic, preserve mode/approval suffixes after capacity replans, and distinguish external overrides from persisted generated prompts. |
@@ -119,7 +120,7 @@ harvest/stewardship commits:
 | #2733 PlanArtifact UI | Mergeable | Locally harvested with richer schema, rendering, relay/fork-state propagation, and replay tests. Comment/close original after integration branch is public, crediting @idling11 and issue #2691; keep #2691 open only if additional PlanReview product work remains. |
 | #2736 sub-agent model inheritance | Mergeable | Locally harvested with parent-model inheritance, explicit override coverage, and strict OpenAI-like `reasoning_effort = off` shaping coverage. Comment/close original after the integration branch is public, crediting @h3c-hexin. |
 | #2737 configured `skills_dir` discovery | Mergeable | Locally harvested with extra configured-before-global precedence tests. Comment/close original after the integration branch is public, crediting @h3c-hexin. |
-| #2738 dense tool-call transcript collapse | Mergeable | Do not merge as-is. The compaction idea matches the `/relay` direction, but the PR currently bypasses normal rendering, lacks expansion wiring, defaults to expanded mode, and has cache-key/index maintenance risks. Harvest only after completing those behaviors. |
+| #2738 dense tool-call transcript collapse | Mergeable / locally harvested | Harvested with normal rendering preserved, expansion wired through Enter/Space/mouse, compact default restored, full-detail index mapping preserved for Alt+V/copy-style paths, and revision keys mixed across hidden cells. Comment/close original after the integration branch is public, crediting @idling11 and issue #2692. |
 
 ## Issue Reduction Strategy
 
@@ -140,6 +141,7 @@ Issue count should drop through evidence-backed consolidation, not bulk closing.
 ## Immediate Next Actions
 
 1. Prepare public comments for #2708, #2502, #2513, #2530, #2576, #2581, #2627,
-   #2634, #2636, #2687, #2736, #2737, and already-harvested performance PRs.
+   #2634, #2636, #2687, #2736, #2737, #2738, and already-harvested performance
+   PRs.
 2. Start file decomposition Phase 1 only after the PR harvest table has no
    unknown high-priority provider/prompt/cache branches.