Add bootapi repository

bootapi is a Go service replacing Cobbler's PXE/kickstart side: it renders
kickstart files and iPXE boot scripts from NetBox data and serves them to
PXE-booting hosts. The ENC half already moved to encapi; bootapi covers the
provisioning/boot half.

Adds config/git.unkin.net/unkin/repository/bootapi.yaml modeled on encapi:
public repo, squash merges, delete-branch-after-merge, main branch protection
requiring the pre-commit/test/build Woodpecker checks and benvin approval.

Claude-Session: https://claude.ai/code/session_015ur3i7D2azsMAWTSVABApv

config/git.unkin.net/unkin/repository/bootapi.yaml

@@ -0,0 +1,14 @@
+description: "PXE/kickstart boot service replacing Cobbler. Renders kickstart + iPXE from NetBox data over HTTP. Go API."
+private: false
+default_branch: "main"
+default_delete_branch_after_merge: true
+default_merge_style: "squash"
+branch_protection:
+  - rule_name: "main"
+    enable_push: false
+    status_check_contexts:
+      - "ci/woodpecker/pr/pre-commit"
+      - "ci/woodpecker/pr/test"
+      - "ci/woodpecker/pr/build"
+    approval_whitelist_users:
+      - "benvin"