BPF CI Bot prompt improvements (#452)

Make the agent prompt more structured. Provide additional instructions about tools, error handling etc.

Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>

Author: theihor

.github/workflows/ai-agent.yml

@@ -9,7 +9,7 @@ permissions:
 
 on:
   schedule:
-    - cron: '0 12 * * 1,3,5'  # Mon/Wed/Fri at ~4am Pacific Time
+    - cron: '0 12 * * 1'  # Monday at ~4am Pacific Time
   workflow_dispatch:
   pull_request:
     paths:
@@ -138,7 +138,7 @@ jobs:
         run: |
           git remote add torvalds https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
           git fetch torvalds
-          MERGE_BASE=$(git merge-base v6.19 HEAD)
+          MERGE_BASE=$(git merge-base torvalds/master HEAD)
           rm -rf /ci/.semcode.db/lore
           ln -s /ci/.semcode.db .semcode.db
           semcode-index --git "${MERGE_BASE}..HEAD"