fix(gitea): restore the withLines exception and route rename_branch through the orchestrator

gitea-files' always-loaded Gotchas said "content is base64 both ways" without
qualification. The `main` text carried an exception for `withLines: true` and both
halves were dropped. Verified live: `get_file_contents` with `withLines: true`
returns plain JSON text while the same response still reports `"encoding":"base64"`.
An agent that follows the recommendation two sentences later and applies the
unconditional decode gets garbage, with the response's own field confirming the
wrong answer. Exception restored, and the lying field named.

gitea-orchestrate was never updated for `rename_branch`: absent from the operation
enum, so an agent caller got "unknown operation", and absent from the
destructive-confirm list, though branches.md requires a rename with open PRs or a
protection rule to be confirmed exactly as `delete_branch` is. Added to both — the
confirm gate rather than the enum alone, because accepting the operation without it
routes around a rule the skill states while appearing to support it. The
compatibility frontmatter, which the agent reads, still omitted the tool too.

Two more always-loaded Gotchas contradicted their own reference files, and the
Gotcha was wrong both times: issues and PRs are distinguishable on a list item by
the `html_url` path segment (confirmed live — #129 at /pulls/, #128 at /issues/),
and `get_repository_tree` takes `tree_sha`, not `ref`.

`review_comments` was asserted as unconditionally present on the PR get response.
It is absent on a PR with no review comments, so the claim is downgraded to
present-when-non-zero rather than stated as response shape.

The label-exclusivity relocation moved the rule out of label-inference.md and into
labels.md without updating sources.md, leaving the one rule in this branch that
writes differently to live repos citing a file that no longer carries it. The rule
itself is correct as it stands and `main` was wrong — every Kind/* label on this
instance is exclusive:false, every Priority/* and Status/* is true — so only the
provenance record is corrected.

Routing: gitea-workflow lost the human-caller discriminator and widened from status
checks to any request, which sent "close #42" to a branch that resolves the number
and presents detail without ever closing it. gitea-branches and gitea-issues regain
trigger phrasings the retrofit dropped.

Refs: #92

plugins/gitea/.apm/skills/gitea-files/references/reading.md

@@ -14,9 +14,13 @@ All three read calls select what to read with `ref` — a branch name, tag, or c
 `get_file_contents(owner, repo, ref, path)`.
 
 The response carries the file's `sha` at the **top level**, not nested under `content`. That field
-is the write-ready SHA, so capture it whenever a write may follow. Content comes back
-base64-encoded — decode it. Pass `withLines: true` only when you need numbered lines to quote
-specific lines back to the user; omit it for a normal content fetch.
+is the write-ready SHA, so capture it whenever a write may follow.
+
+Content comes back base64-encoded — decode it — **unless `withLines: true` was passed**, in which
+case `content` is already plain text: a JSON array of `{"line": N, "content": "..."}` objects.
+The response reports `"encoding": "base64"` either way, so that field is wrong under `withLines`
+and decoding on its word yields garbage. Pass `withLines: true` only when you need numbered lines
+to quote specific lines back to the user; omit it for a normal content fetch.
 
 ## One directory level