docs: fix write-good.So/ThereIs/Weasel lint findings

Fixes the "obvious ones first" slice of #4042 (mara: do the obvious
ones first) -- 81 hits across write-good.So, write-good.ThereIs, and
write-good.Weasel, all in docs/. Each is a genuine sentence rewrite
(lead with the real subject instead of "There is/are", drop a
sentence-initial "So ", replace a vague intensifier), not a blind
regex substitution -- read every hit in its real file context before
touching it.

3 of the 81 hits were in CI-generated CLI docs (docs/tools/{hivectl,
swarmctl,forge}-cli.md) -- fixed at the clap #[arg(...)]/doc-comment
source in hivectl/src/cli.rs, swarmctl/src/main.rs, and
hive-forge/src/verbs/repo_add_collaborator.rs, then regenerated via
each crate's `markdown-docs` subcommand so CI's freshness check stays
green.

Verified: fresh vale re-run shows 0 remaining So/ThereIs/Weasel hits
and no new hits introduced (983->982, exactly the one incidental fix
this pass also picked up at docs/scheduler/observability.md:48).
cargo fmt --check and clippy clean on the three touched crates.

Remaining write-good backlog (Passive: 726, TooWordy: 207) is
judgment-heavy and left for a follow-up slice of #4042, not bulk-
rewritten here.

docs/turn-loop/claude-invocation.md

@@ -25,7 +25,7 @@ to the bus.
 **Which `claude` binary.** The bare name `claude`, resolved off the
 harness unit's PATH. By default that's the `claude-code` in the agent's
 own nixpkgs (the meta flake's `nixpkgs` input) via
-`environment.systemPackages`. Since that's usually a release channel and
+`environment.systemPackages`. Since that's typically a release channel and
 this package moves fast, the operator can pin one hive-wide with
 `services.hyperhive.c0re.claudeCodePackage`: its store path is written
 into each agent's flake, and `claude` on PATH becomes a symlink to it
@@ -117,7 +117,7 @@ into its `run`:
   _still_ overflows, `run` surfaces `Error::PromptTooLong`; `drive_turn`
   then archives the session (session lifecycle stays hive-side) and the
   serve loop requeues the message so it redelivers into a fresh session
-  (see [Turn outcomes](README.md#turn-outcomes) — the wake prompt itself is tiny, so
+  (see [Turn outcomes](README.md#turn-outcomes) — the wake prompt itself is small, so
   the overflow was the accumulated context the archive clears).
 - **Proactive** — a turn finishes cleanly but the last inference's context
   size crossed the policy watermark. While the session is still healthy it
@@ -185,7 +185,7 @@ still applies.
   exceeds the assumed prompt-cache TTL (`HIVE_CACHE_TTL_SECS`, default
   `3600`). Claude's prompt cache goes cold after a while; once it's cold,
   `--resume`-ing a large session pays the full re-upload cost with no
-  benefit over starting fresh. So `drive_turn` **archives** the current
+  benefit over starting fresh. `drive_turn` **archives** the current
   session (same mechanism as the operator reset — rename `<uuid>.jsonl` →
   `.archived`) so the next turn's `--resume <title>` misses and starts
   fresh. Unlike proactive compaction the session is dropped entirely, not