chore: define stale PR policy and clean up inactive PRs

[andreahlert]

Part of #690

Establish a stale PR policy and apply it to the current backlog.

Policy

• PRs with review comments and no author response for 14 days → pr/stale → convert to draft
• PRs with no activity for 90 days → lifecycle/stale → close with comment inviting reopen
• Umbrella/roadmap PRs can be marked lifecycle/frozen to exempt from auto-close

Progress

Closed (2026-03-28):

• Docs/general update #565 (Docs/general update) — superseded by Update project references to Apache Burr and remove DAGWorks attributions #659
• Version bump to 0.41.0 #596 (Version bump 0.41.0) — obsolete, 0.42.0 prep merged
• WIP for fixing partition key link -- assumes it is the same as the pa… #519, scratch pad for fixing partition key with local tracker #330 (partition key fixes) — superseded by fix: pass partition_key to child PointerModel in fork/spawn relationships #682
• New Graph Builder Tool in Burr UI #572, Refactor GraphView component to be identical to the GraphBuilder component #573 (Graph Builder) — superseded by feat: add visual Graph Builder tool to Burr UI #667
• Update Instructor + Gemini example #267, WIP for tools #143, WIP snake example #49, Adds default reads/writes to burr actions #269, Playground for auto-generating FastAPI apps #365 (stale drafts from elijahbenizzy) — 18-24 months inactive
• Added Favicon #401 (favicon) — superseded by new website
• Adds endpoints to debug what has been persisted #291 (debug endpoints) — 20 months inactive
• Parallel streams WIP not ready #533 (parallel streams WIP) — 11 months inactive
• WIP fix for #443 #444 (WIP fix for Bug in async lifecycle hooks with synchronous implementation #443) — draft since Nov 2024, no code changes
• WIP typescript implementation #610 (WIP TypeScript) — inactive

Dependabot PRs cleaned up (2026-03-28):
12 stale dependabot PRs closed, 3 new ones remain active (#658, #700, #702).

Remaining

• Apply pr/stale label to PRs that match the 14-day rule going forward
• Set up automation to flag stale PRs (optional, can be manual triage pass)

Related

• Issue assignment policy: chore: define issue assignment policy #709

[andreahlert]

Labels migrated to new taxonomy (#692).