…7510)

Follow-up to zed-industries#57466 simplifying `load_skill_frontmatter` rather than
fixing a separate bug.

zed-industries#57466 fixed the chunked-read loop so it truncates accumulated bytes at
the frontmatter boundary, preventing `str::from_utf8` from failing on a
multi-byte grapheme split across chunks. That fix is correct, but the
chunked read it's working around isn't pulling its weight:
`MAX_SKILL_FILE_SIZE` is 100KB and there's already a metadata pre-check,
so "stop reading early once we've seen the closing `---`" saves at most
~25 pages per file while forcing the use of `open_sync`, a hand-rolled
loop, and a long comment about `smol::unblock` vs the GPUI test
scheduler.

This PR:

- replaces the chunked `open_sync` + read loop with a single
`fs.load(...)` call (the same primitive `read_skill_body` already uses);
- deletes `closing_delimiter_end`, `SKILL_READ_CHUNK_SIZE`, the
`std::io::{self, Read}` import, and the `Parking forbidden` paragraph;
- tightens the metadata pre-check so a metadata error (permissions, I/O,
etc.) bails out instead of silently falling through to a blind read;
- removes the now-obsolete
`test_load_skill_frontmatter_with_emoji_at_chunk_boundary` test — by
construction, a single full read can't split a UTF-8 sequence at any
boundary.

Closes AI-303

Release Notes:

- N/A

…pick to preview) (#57831)

Cherry-pick of #57510 to preview

----
Follow-up to #57466 simplifying `load_skill_frontmatter` rather than
fixing a separate bug.

the frontmatter boundary, preventing `str::from_utf8` from failing on a
multi-byte grapheme split across chunks. That fix is correct, but the
chunked read it's working around isn't pulling its weight:
`MAX_SKILL_FILE_SIZE` is 100KB and there's already a metadata pre-check,
so "stop reading early once we've seen the closing `---`" saves at most
~25 pages per file while forcing the use of `open_sync`, a hand-rolled
loop, and a long comment about `smol::unblock` vs the GPUI test
scheduler.

This PR:

- replaces the chunked `open_sync` + read loop with a single
`fs.load(...)` call (the same primitive `read_skill_body` already uses);
- deletes `closing_delimiter_end`, `SKILL_READ_CHUNK_SIZE`, the
`std::io::{self, Read}` import, and the `Parking forbidden` paragraph;
- tightens the metadata pre-check so a metadata error (permissions, I/O,
etc.) bails out instead of silently falling through to a blind read;
- removes the now-obsolete
`test_load_skill_frontmatter_with_emoji_at_chunk_boundary` test — by
construction, a single full read can't split a UTF-8 sequence at any
boundary.

Closes AI-303

Release Notes:

- N/A

…k boundary (zed-industries#57466)

Self-Review Checklist:

- [X] I've reviewed my own diff for quality, security, and reliability
- [X] Unsafe blocks (if any) have justifying comments
- [X] The content is consistent with the [UI/UX
checklist](https://github.com/zed-industries/zed/blob/main/CONTRIBUTING.md#uiux-checklist)
- [X] Tests cover the new/changed behavior
- [X] Performance impact has been considered and is acceptable

Closes zed-industries#57463

Release Notes:

- Fixed utf-8 parsing issues when loading skill frontmatter with
multi-codepoint graphemes (such as an emoji) crossing file chunk load
boundaries.

…7510)

Follow-up to zed-industries#57466 simplifying `load_skill_frontmatter` rather than
fixing a separate bug.

zed-industries#57466 fixed the chunked-read loop so it truncates accumulated bytes at
the frontmatter boundary, preventing `str::from_utf8` from failing on a
multi-byte grapheme split across chunks. That fix is correct, but the
chunked read it's working around isn't pulling its weight:
`MAX_SKILL_FILE_SIZE` is 100KB and there's already a metadata pre-check,
so "stop reading early once we've seen the closing `---`" saves at most
~25 pages per file while forcing the use of `open_sync`, a hand-rolled
loop, and a long comment about `smol::unblock` vs the GPUI test
scheduler.

This PR:

- replaces the chunked `open_sync` + read loop with a single
`fs.load(...)` call (the same primitive `read_skill_body` already uses);
- deletes `closing_delimiter_end`, `SKILL_READ_CHUNK_SIZE`, the
`std::io::{self, Read}` import, and the `Parking forbidden` paragraph;
- tightens the metadata pre-check so a metadata error (permissions, I/O,
etc.) bails out instead of silently falling through to a blind read;
- removes the now-obsolete
`test_load_skill_frontmatter_with_emoji_at_chunk_boundary` test — by
construction, a single full read can't split a UTF-8 sequence at any
boundary.

Closes AI-303

Release Notes:

- N/A