docs(code-review): expand story file validation to include empty and malformed files

Skip to substep 5 correctly communicates jumping past the rest of the git
discovery logic in substep 4 when git repo is not found. Proceed would
suggest normal sequential flow, but we are skipping the conditional branch.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

src/modules/bmm/workflows/4-implementation/code-review/steps/step-01-load-story.md

@@ -13,6 +13,7 @@ These variables MUST be set in this step and available to all subsequent steps:
 
 - `story_path` - Path to the story file being reviewed
 - `story_key` - Story identifier (e.g., "1-2-user-authentication")
+- `story_content` - Complete, unmodified file content from story_path (loaded in substep 2)
 - `story_file_list` - Files claimed in story's Dev Agent Record → File List
 - `git_changed_files` - Files actually changed according to git
 - `git_discrepancies` - Mismatches between `story_file_list` and `git_changed_files`
@@ -27,13 +28,13 @@ Ask user: "Which story would you like to review?"
 
 **Try input as direct file path first:**
 If input resolves to an existing file:
-  - Verify it's in `sprint_status` with status `review` or `done`
+  - Verify it's in {sprint_status} with status `review` or `done`
   - If verified → set `story_path` to that file path
-  - If NOT verified → Warn user the file is not in sprint_status (or wrong status). Ask: "Continue anyway?"
+  - If NOT verified → Warn user the file is not in {sprint_status} (or wrong status). Ask: "Continue anyway?"
     - If yes → set `story_path`
     - If no → return to user prompt (ask "Which story would you like to review?" again)
 
-**Search sprint_status** (if input is not a direct file):
+**Search {sprint_status}** (if input is not a direct file):
 Search for stories with status `review` or `done`. Match by priority:
 1. Story number resembles input closely enough (e.g., "1-2" matches "1 2", "1.2", "one dash two", "one two"; "1-32" matches "one thirty two"). Do NOT match if numbers differ (e.g., "1-33" does not match "1-32")
 2. Exact story name/key (e.g., "1-2-user-auth-api")
@@ -47,50 +48,69 @@ Search for stories with status `review` or `done`. Match by priority:
 
 ### 2. Load Story File
 
-- Read COMPLETE story file from {story_path}
-- Extract `story_key` from filename (e.g., "1-2-user-authentication.md" → "1-2-user-authentication") or story metadata
+**Load file content:**
+Read the complete contents of {story_path} and assign to `story_content` WITHOUT filtering, truncating or summarizing. If {story_path} cannot be read, is empty, or obviously doesn't have the story: report the error to the user and HALT the workflow.
 
-### 3. Parse Story Sections
+**Extract story identifier:**
+Verify the filename ends with `.md` extension. Remove `.md` to get `story_key` (e.g., "1-2-user-authentication.md" → "1-2-user-authentication"). If filename doesn't end with `.md` or the result is empty: report the error to the user and HALT the workflow.
 
-Extract and store:
+### 3. Extract File List from Story
 
-- **Story**: Title, description, status
-- **Acceptance Criteria**: All ACs with their requirements
-- **Tasks/Subtasks**: All tasks with completion status ([x] vs [ ])
-- **Dev Agent Record → File List**: Claimed file changes
-- **Change Log**: History of modifications
+Extract `story_file_list` from the Dev Agent Record → File List section of {story_content}.
 
-Set `story_file_list` = list of files from Dev Agent Record → File List
+**If Dev Agent Record or File List section not found:** Report to user and set `story_file_list` = NO_FILE_LIST.
 
 ### 4. Discover Git Changes
 
 Check if git repository exists.
 
-**If NOT a git repo:** Set `git_changed_files` = NO_GIT, `git_discrepancies` = NO_GIT. Skip to substep 6.
+**If NOT a git repo:** Set `git_changed_files` = NO_GIT, `git_discrepancies` = NO_GIT. Skip to substep 5.
 
 **If git repo detected:**
 
 ```bash
 git status --porcelain
-git diff --name-only
-git diff --cached --name-only
+git diff -M --name-only
+git diff -M --cached --name-only
 ```
 
-Compile `git_changed_files` = union of modified, staged, and new files.
+If any git command fails: Report the error to the user and HALT the workflow.
+
+Compile `git_changed_files` = union of modified, staged, new, deleted, and renamed files.
 
 ### 5. Cross-Reference Story vs Git
 
-Compare {story_file_list} with {git_changed_files}:
+**If {git_changed_files} is empty:**
+
+Ask user: "No git changes detected. Continue anyway?"
+
+- If **no**: HALT the workflow
+- If **yes**: Continue to comparison
+
+**Compare {story_file_list} with {git_changed_files}:**
+
+Exclude git-ignored files from the comparison (run `git check-ignore` if needed).
 
 Set `git_discrepancies` with categories:
 
 - **files_in_git_not_story**: Files changed in git but not in story File List
-- **files_in_story_not_git**: Files in story File List but no git changes
+- **files_in_story_not_git**: Files in story File List but no git changes (excluding git-ignored)
 - **uncommitted_undocumented**: Uncommitted changes not tracked in story
 
-### 6. Load Project Context
+---
 
-- Load {project_context} if exists (**/project-context.md) for coding standards
+## COMPLETION CHECKLIST
+
+Before proceeding to the next step, verify ALL of the following:
+
+- `story_path` identified and loaded
+- `story_key` extracted
+- `story_content` captured completely and unmodified
+- `story_file_list` compiled from Dev Agent Record (or NO_FILE_LIST if not found)
+- `git_changed_files` discovered via git commands (or NO_GIT if not a git repo)
+- `git_discrepancies` calculated
+
+**If any criterion is not met:** Report to the user and HALT the workflow.
 
 ---
 
@@ -100,24 +120,3 @@ Set `git_discrepancies` with categories:
 
 "**NEXT:** Loading `step-02-build-attack-plan.md`"
 
----
-
-## SUCCESS METRICS
-
-- `story_path` identified and loaded
-- `story_key` extracted
-- All story sections parsed
-- `story_file_list` compiled from Dev Agent Record
-- `git_changed_files` discovered via git commands
-- `git_discrepancies` calculated
-- `project_context` loaded if exists
-- Explicit NEXT directive provided
-
-## FAILURE MODES
-
-- Proceeding without story file loaded
-- Missing `story_key` extraction
-- Not parsing all story sections
-- Skipping git change discovery
-- Not calculating discrepancies
-- No explicit NEXT directive at step completion