fix: goal-creator now emits task_identifier

[bborbe]

Problem

goal-creator never emitted task_identifier, so every goal it created failed goal lint on the first check:

ERROR 23 Goals/<goal>.md: MISSING_TASK_IDENTIFIER task_identifier is missing; run backfill to assign one

goal lint --fix does not repair it, so the operator has to generate a UUID by hand and run goal set.

task-creator.md has carried the equivalent instruction all along (agents/task-creator.md:120) — the goal side was simply missing it.

Fix

One line added to the required-frontmatter list in agents/goal-creator.md, mirroring the task-creator wording.

Evidence

Found 2026-08-17 while scaffolding a goal via /jira-sprint-sync: all five sibling tasks created by task-creator in the same run linted clean, and only the goal failed.

Not fixed here

The lint hint names a backfill command that does not exist on vault-cli goal, and goal lint --fix reports MISSING_TASK_IDENTIFIER as fixable without fixing it. Both are Go-side; this change makes the common path moot but does not address them.

[bborbe]

Closing unmerged — the premise was wrong.

I proposed this after goal lint failed a freshly created goal with MISSING_TASK_IDENTIFIER, and agents/task-creator.md carried the instruction while goal-creator.md did not. I treated that asymmetry as the defect. It isn't.

Checking what goals actually contain:

• 19 goals in the Brogrammers vault; 1 carries task_identifier — the one I set by hand while investigating.
• goal_identifier: appears in 6 goals across vaults. That, not task_identifier, is the goal-side key.

So this PR would have written a task-shaped key onto every future goal.

The real defect is in the linter: pkg/ops/lint.go runs missingTaskIdentifierIssues on every file with no page-type branch, and detectMissingTaskIdentifier unmarshals only yaml:"task_identifier". Goals get checked for the wrong key — all 19 fail it, not just newly created ones. grep -rn goal_identifier --include='*.go' returns nothing, so the Go side has never modelled the key goals actually use.

Two adjacent findings for whoever picks up the real fix:

• pkg/storage/task.go:44 auto-generates the UUID in WriteTask when empty; WriteGoal in pkg/storage/goal.go has no equivalent.
• EnsureAllTaskIdentifiersOperation exists in pkg/ops but is wired to no CLI command, so the lint hint "run backfill to assign one" names something uninvokable.

Correct fix: make the identifier check page-type aware, or unify both page types behind one neutral key. Either needs a spec, not a one-line agent edit.

[ben-s-pull-request-reviewer]

I now have all the information needed for a thorough review.

Summary of review:

The diff contains exactly two files: CHANGELOG.md (one changelog bullet) and agents/goal-creator.md (one instruction line added to the "Required fields" list in step 8).

Key architectural facts established by code inspection:

1. GoalFrontmatter has no TaskIdentifier() accessor — unlike TaskFrontmatter which has both TaskIdentifier() and SetTaskIdentifier(). However, GoalFrontmatter embeds FrontmatterMap and uses GetString(key) for unknown fields, so task_identifier written by the agent will survive round-trips via the generic path (e.g., GetField("task_identifier")). The field is not lost — it's just not accessed via a typed method.

2. No Go code creates goals — domain.NewGoal() takes a plain map[string]any; callers populate it. The goal-creator agent (a markdown/Claude instruction file) is what generates the actual file content. The fix is correctly placed in the agent instruction file.

3. MISSING_TASK_IDENTIFIER fixability — Fixable: false is intentional (auto-minting a UUID would silently change identity). The lint message says "run backfill" but the changelog accurately notes this command does not exist. This is a pre-existing UX defect in lint.go:621, not introduced by this PR, and correctly documented in the changelog.

4. Changelog accuracy — The bullet accurately describes the bug, the discovery context, and the two related observations (sibling tasks linting clean; backfill command absent).

---

{
  "verdict": "approve",
  "summary": "Clean documentation-only fix. The goal-creator agent now instructs itself to emit `task_identifier` in generated goal frontmatter, matching the existing convention in task-creator. No Go code changes; the field survives round-trips via FrontmatterMap. The changelog entry accurately describes the bug, its discovery context, and the related backfill-command UX issue.",
  "comments": [],
  "concerns_addressed": [
    "correctness: agents/goal-creator.md is documentation-only (markdown agent definition); confirmed — no Go code creates goals, the agent instruction is the correct fix location",
    "correctness: goal lint --fix reports MISSING_TASK_IDENTIFIER as fixable without actually fixing it — accurately documented in the CHANGELOG.md bullet; pre-existing lint.go UX defect, not introduced by this PR"
  ]
}