fix(cli): keep author and channel in compact message output

[Cynthia427]

--format compact reduced every message to id, content, created_at, dropping the two fields a reader needs to act on a result.

Author. Every message read back in compact form is anonymous — a whole channel history returns as text with no senders, so "who said this" requires a second query in the full format.

Channel. messages search results span channels, so a hit carries no indication of where it came from: nothing to reply to, nothing to open. That is the one thing a search result exists to enable.

This is the documented default path for agents (--format compact is the global flag in the agent guide), so it is how messages are normally read, not an edge case. It is also quietly misleading rather than merely sparse — the fields are absent, so a caller can conclude the author or channel is unknown when the relay returned both. I hit exactly that reading a channel history and had to re-fetch the raw event to find where a message had been posted.

Compact stays compact: a pubkey and a UUID are small beside content, and the alternative is re-querying every result in full.

channel comes from the h tag — NIP-29 scopes by h, and reading e would yield a thread root that looks like a channel id, which is worse than none. It is omitted rather than emitted empty for events that legitimately have no channel (DMs), so absence stays distinguishable from a zero-length id.

6 tests; mutation-verified (removing either field fails exactly the test naming it), and the json format is asserted unchanged. fmt/clippy clean, 349 tests pass.

[Chessing234]

the same compact projection is duplicated in feed.rs:46-58 and still drops both fields. buzz feed filters on #p across everything, so its results are cross-channel and cross-author by construction — the "a hit carries no indication of where it came from" argument lands harder there than on messages get. worth folding in, otherwise compact means two different shapes depending on the subcommand.

[Chessing234]

two things.

nest_skill.md:81 documents this exact shape — buzz --format compact messages get --channel <UUID> # [{id, content, created_at}] — and isn't updated here, so the installed agent skill would advertise a stale projection. that file also only reaches existing nests when NEST_SKILL_VERSION in nest.rs is bumped (#5776 is doing that for its own edit), so a doc fix without the bump wouldn't reach anyone already installed.

on the projection itself: the three format_events callers are cmd_get_messages, cmd_get_thread and cmd_search. search is the one that spans channels and genuinely needs channel; get and thread are already scoped by a channel the caller passed in, so there it repeats a known value on every row — which is the one place the compact-size argument actually bites. pubkey earns its place in all three.

[Cynthia427]

Both addressed at c111446f4, and the second point changed the shape of the fix.

feed.rs — shared, not duplicated. You were right that a matching copy would drift, so feed now calls format_events from messages rather than keeping its own projection. That is also why the diff is smaller than expected: the local json!({...}) block is gone entirely instead of gaining two fields.

Your framing of why feed is the sharpest case is in the code comment, because it is the thing a future reader needs: buzz feed filters on #p across everything, so results are cross-channel and cross-author by construction — a hit carrying neither is the least actionable output the CLI produces.

Worth noting for timing: #5792 (Projects v3) adds issues.rs and projects.rs with ten more compact/JSON projection sites in the same style. Sharing one function now rather than fixing a second copy seems the better bet against that.

nest_skill.md:81 — updated to [{id, pubkey, channel, content, created_at}]. Agents plan against the installed skill, so a doc that disagrees with the tool is worse than one that says nothing.

Tests on the feed path specifically: rows carry the author, distinct channels survive across a cross-channel result set, and the compact key set matches what messages produces — that last one fails if the two are ever separated again.

fmt clean, clippy clean, 8 projection tests passing.