[kitlangton]

Captures no longer claim things that didn't happen: Undo can't outlive a rule's send, a shot's marks are never silently dropped, and "Copied" appears only once the clipboard has it.
Three small honesty fixes in the capture capsule and the screenshot editor. Routing, recording and transcription are unchanged.

❌ Before

1. A capture matched a saved rule. The Undo ring counted 5 s, but the send went out after 3 s ❌, so the last 2 s of Undo did nothing.
2. If a screenshot's marks couldn't be drawn, the editor copied, saved or sent the plain screenshot ❌ and said it had worked.
3. Cards said "Copied" before the clipboard write ran ❌, and the capsule said "Copied" even when the write failed ❌. It also never said what was copied: the capsule copies a text summary, not the movie.

✅ After

1. The Undo ring and the send share one 3 s window. Undo disappears as soon as the send starts.
2. A failed mark render exports nothing. The editor shows "Couldn't draw your marks" in red with a Retry button until the next export.
3. Cards say "Copied" (a shot) or "Movie copied" (a recording) after the write succeeds, or "Couldn't copy". The capsule says "Summary copied", or "Couldn't copy" with a warning. Paste still works from there, because it copies again.

- ring = undo_s() (5 s)             ; send after SEND_HOLD (3 s)
+ ring = SEND_HOLD, counted from when the rule's answer arrives; Undo hides on Sending
- png() -> marks failed? -> plain image
+ png() -> marks failed? -> MarksNotDrawn -> red note + Retry, nothing exported
- note("Copied"); copy(file)        ; capsule: copy() then "Copied" regardless
+ copy(file) -> Ok ? "Copied"/"Movie copied" : "Couldn't copy"; capsule: "Summary copied" | "Couldn't copy"

📊 Proof

Case	Before	After
Undo pressed 4 s after a rule matched	❌ send already gone	✅ Undo already hidden at 3 s
Rule's answer arrives late	❌ hold counted from the write	✅ hold counted from the answer
Marks can't be drawn	❌ plain image exported	✅ nothing exported, error + Retry
Clipboard write fails	❌ "Copied"	✅ "Couldn't copy"

Rule send, before and after (the ring now drains over 3 s):

Editor when marks can't be drawn (new state):

Capsule after a capture: before, after, and a failed copy:

New tests: a late rule answer holds its send from the answer, a shot whose marks can't be drawn isn't exported, a failed export stays until retried, and a failed copy never reads as copied (flow and feed). They weren't run against the old code.

👀 Read: routing/preparation.rs, where the send's deadline is set when a rule's answer arrives. It used to be set at write time, so a slow answer ate into Undo. One known harmless race: an Undo pressed in the single frame between the post and the capsule seeing it becomes a withdraw. A guess's post-send withdraw keeps its own 5 s window on purpose. The rest is routine.

_{🔍 Found in a UX audit of captures · no user reports · goldens: capsule ones regenerated on a Mac, the new editor one from the Linux check}

Checks run

• scripts/check capture_capsule routing (bug 1): 314 passed

• cargo nextest run capture_capsule screenshot_thumbnail capture_host i18n: 282 passed (plus one ignored routing benchmark that timed out, not part of this change)

• cargo clippy --all-targets -D warnings: clean

• Check Linux (full suite, goldens from its golden-actual): test job passed. Its nix job fails only on onboarding_kit::stories::motion_gate::the_first_run_moves_cleanly, which fails the same way on other branches (scrub-fixtures), so this change didn't cause it