chore(bots): drop hardcoded flow-aware templates from .bot/config.yaml

Post-#110 the engine resolves branch_prefix / pr_title_template /
commit_message_template per-flow, and its bug-fix defaults are byte-identical to
what we hardcoded (branch `ai/bugfix-issue-`, title/commit `fix: …`). Omitting
them is behavior-preserving for our bug-fix flow AND future-proofs other flows
(a task/Feature run gets the engine's `feat:` templates instead of a misleading
`fix:` prefix). pr_body_template stays (no engine default); flow: bug-fix unchanged.

Also fix a stale comment in engineer-bot-followup.yml (checkout step referenced
the removed bot-run composite).

(Engine pin d24ca21 + Type-based flow selection already on this branch.)

Signed-off-by: Eric Wang <e.wang@databricks.com>
Co-authored-by: Isaac
Signed-off-by: eric-wang-1990 <e.wang@databricks.com>

Author: eric-wang-1990

.bot/config.yaml

@@ -4,20 +4,25 @@
 # .bot/prompts/review/system.md); only the engineer-bot is config-driven.
 name: databricks_sql_python_bugfix
 marker_namespace: engineer-bot-python
-branch_prefix: ai/bugfix-issue-
 bot_login_prefix: peco-engineer-bot
 max_replies_per_thread: 5
 
+# branch_prefix / pr_title_template / commit_message_template are OMITTED: they
+# are flow-aware templates, and the engine's per-flow defaults already match what
+# we'd hardcode (bug-fix ⇒ branch `ai/bugfix-issue-`, title/commit `fix: …`).
+# Omitting them keeps that behavior AND future-proofs other flows — a task/Feature
+# run gets the engine's `feat:` templates instead of a misleading `fix:` prefix.
+# Add a string (all flows) or a {flow: template} map here only to override.
+
 # safe_path denylist. Only the always-on hard-denied prefixes apply here
 # (.git/ and .gitleaksignore), seeded by the engine regardless — so this key is
 # omitted. Everything else under the repo root is writable; the safeguard is the
 # human PR-review gate, not a tool-layer block. Reviewers MUST scrutinize any
 # agent-authored diff reaching .github/, .bot/, or pyproject.toml. To hard-block
 # a path at the tool layer, add it under `denied_subpaths:` (repo-relative).
 
-# Filled from the tracking ISSUE the maintainer labelled.
-pr_title_template: "fix: {issue_title} (#{issue_number})"
-commit_message_template: "fix: resolve #{issue_number}"
+# Filled from the tracking ISSUE the maintainer labelled. (pr_body_template has no
+# engine default, so it stays required here.)
 pr_body_template: |-
   ## Summary
 

.github/workflows/engineer-bot-followup.yml

@@ -77,7 +77,8 @@ jobs:
     steps:
       # Checkout FIRST (remote action) so the local `./` composites resolve.
       # Check out the PR head BRANCH (not the merge ref) so fixups push back to
-      # it; bot-run re-establishes the authenticated push remote.
+      # it. persist-credentials:false; the run step below sets an authenticated
+      # push remote from the minted App token.
       - name: Checkout PR head branch
         uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0  # v7.0.0
         with: