fix(#2376): emit absolute subagent-facing paths from init/state, convert workflow literals (#2428)

* fix(#2376): emit absolute subagent-facing init/state paths

Make init.* and state.* path fields absolute rather than cwd-relative
so subagent prompts resolve correctly regardless of working directory.
Adds intel_dir/conflicts_path/requirements_path/roadmap_path/state_path
to cmdInitIngestDocs, an absolute debug_dir to cmdStateLoad, and
replaces bare .planning/... literals in 12 workflow Agent() prompt
blocks with the absolute init-JSON path fields. Includes decoy-cwd
regression tests and realpath'd tmpdir fixtures for macOS.

Squashed rebase of the #2376 commit series onto a fresh origin/next
(previous merge ee25543a1 was against a now-stale next).

* chore(#2376): add changeset

* chore(#2376): regenerate golden fixtures + workflow size baseline

Regenerated after rebasing the absolute-path fix onto current next
(picks up #2351's run-with-timeout content in execute-phase.md too).

* fix(#2376): trim execute-phase.md redundancy to stay under the size margin

* chore(#2376): regenerate golden/size baseline after rebase onto next

gsd-core/workflows/verify-work.md

@@ -48,7 +48,7 @@ AGENT_SKILLS_PLANNER=$(gsd_run query agent-skills gsd-planner)
 AGENT_SKILLS_CHECKER=$(gsd_run query agent-skills gsd-plan-checker)
 ```
 
-Parse JSON for: `planner_model`, `checker_model`, `commit_docs`, `phase_found`, `phase_dir`, `phase_number`, `phase_name`, `has_verification`, `uat_path`.
+Parse JSON for: `planner_model`, `checker_model`, `commit_docs`, `phase_found`, `phase_dir`, `phase_number`, `phase_name`, `has_verification`, `uat_path`, `state_path`, `roadmap_path`.
 
 ```bash
 # MVP mode detection via the centralized phase.mvp-mode resolver.
@@ -749,8 +749,8 @@ Agent(
 
 <files_to_read>
 - {phase_dir}/{phase_num}-UAT.md (UAT with diagnoses)
-- .planning/STATE.md (Project State)
-- .planning/ROADMAP.md (Roadmap)
+- {state_path} (Project State)
+- {roadmap_path} (Roadmap)
 </files_to_read>
 
 ${AGENT_SKILLS_PLANNER}