`pr review <n>` gains `--comments-file <path>`, a JSON array of inline
comments submitted with the review. Each entry is one of two exclusive
shapes: a new comment `{ path, line, body }` (mapped to `new_position`,
always the new side) or a reply `{ reply_to, body }`. A reply carries no
line or side — gitea-axi finds the target via the reviews-plus-comments
fan-out (there is no get-comment-by-id endpoint), reconstructs its anchor
from the target's own `diff_hunk`, and infers old/new side from it, so a
same-line post threads with the existing conversation. All entries map
onto the review-submission payload's `comments[]`; no new HTTP layer is
added. An unknown `reply_to` is a VALIDATION_ERROR raised before the POST,
and the submitted inline-comment count rides the action block.
The shared path-resolve-and-read behind --body-file and --comments-file is
extracted into src/flag-file.ts.
Each inline review comment under `pr view <n> --reviews` now renders its
`id` (the handle a reply targets), `resolved` (`yes`/`no`, from whether
Gitea populated the comment's `resolver`), and `diff_hunk`. The hunk is
structurally trimmed to its `@@` header line plus its last two lines by
default (hunks of three lines or fewer are left whole) and emitted
verbatim under `--full`, so the trim never touches the char-based body
truncation path. The raw `position`/`original_position` diff offsets stay
unsurfaced. The fields ride the existing reviews-plus-per-review-comments
fetch — no extra API calls.
Add the two PR commands that touch content and the local worktree:
- `pr diff <n>` fetches the raw diff from the `.diff` endpoint (forcing a
text response, which the JSON-defaulting client would otherwise discard),
truncates at 4000 chars with separate `truncated`/`original_length` fields
and a prepended `--full` suggestion; `--full` returns the raw diff.
- `pr checkout <n>` reads the PR head branch from the PR fetch and fetches
`refs/pull/{n}/head` from origin (uniform for same-repo and fork PRs, ADR
0011), three-cased on local branch state so re-checkout is idempotent and
divergent local commits fail with `GIT_ERROR` rather than being discarded.
Introduces the `GIT_ERROR` mapping (`runGit`) carrying git's first stderr
line plus a remediation help line, and widens the PR 404 classifier so a
`.diff` path still resolves to `PR_NOT_FOUND`.
