Allowlist greenlight bot in reviewer action

- Add allowed_bots: pytorchgreenlight[bot] to the claude-code-action step
- Import TARGET_REPO into dispatch.py
- Name the reviewed repo (pytorch/pytorch#N) in dispatch log + error

Notes:
The scan dispatches greenlight-pr-review.yml as the pytorchgreenlight App
bot; claude-code-action blocks bot-triggered runs unless the login is
allowlisted, so the review agent was being silently skipped. Scope to our
own bot rather than "*" so no other external App can trigger reviews on
this public repo. The dispatch messages previously only showed the
dispatch repo/ref; adding TARGET_REPO disambiguates where the workflow
runs (pytorch/test-infra) from which PR it reviews (pytorch/pytorch).

Signed-off-by: Jean Schmidt <contato@jschmidt.me>

Author: jeanschmidt

.github/workflows/greenlight-pr-review.yml

@@ -223,6 +223,10 @@ jobs:
           github_token: ${{ secrets.GITHUB_TOKEN }}
           use_bedrock: "true"
           show_full_output: "true"
+          # The scan dispatches this as the pytorchgreenlight App bot, which
+          # claude-code-action blocks unless allowlisted. Scope to our bot only:
+          # "*" would let any external App trigger reviews on this public repo.
+          allowed_bots: "pytorchgreenlight[bot]"
           claude_args: >-
             --model global.anthropic.claude-opus-5
             --effort high

greenlight/src/greenlight/dispatch.py

@@ -13,7 +13,7 @@
 from typing import TYPE_CHECKING, Protocol
 
 from greenlight import constants
-from greenlight.constants import DEFAULT_DISPATCH_REF, DISPATCH_REPO, WORKFLOW_FILE
+from greenlight.constants import DEFAULT_DISPATCH_REF, DISPATCH_REPO, TARGET_REPO, WORKFLOW_FILE
 
 if TYPE_CHECKING:
 
@@ -59,6 +59,6 @@ def dispatch_review(
     dispatched = workflow.create_dispatch(ref, inputs=inputs, throw=True)
     if not dispatched:
         raise RuntimeError(
-            f"workflow_dispatch for {WORKFLOW_FILE} on {DISPATCH_REPO}@{ref} (PR #{pr_number}) returned failure"
+            f"dispatch of {WORKFLOW_FILE} ({DISPATCH_REPO}@{ref}) to review {TARGET_REPO}#{pr_number} returned failure"
         )
-    logger.info("dispatched %s on %s@%s for PR #%d", WORKFLOW_FILE, DISPATCH_REPO, ref, pr_number)
+    logger.info("dispatched %s (%s@%s) to review %s#%d", WORKFLOW_FILE, DISPATCH_REPO, ref, TARGET_REPO, pr_number)