[alfirus]

Summary

Fixes #141: To/Cc/Bcc were fixed-height (40px) single-line fields, so once the recipient list exceeded the field width it could neither expand to another line nor be reviewed before sending. Recipient rows now wrap and grow (up to five lines, then clip), and the send path accepts newline-separated addresses, so wrapped/pasted lists parse instead of failing or — worse — passing validation as one glued address.

Change

• ui/components/composer-controls.slint — RecipientRow is now multi-line (single-line: false, wrap: word-wrap). Row height tracks an invisible wrapping twin (field-mirror, same origin/font/wrapping, 4px narrower so it never wraps less), min(132px, max(40px, …)), clip: true. Single-line rows render exactly 40px as before.
• ui/components/composer-fields.slint — Cc/Bcc rows stack below the To row's actual height (Cc/Bcc are now always-instantiated with visible instead of if, so their heights are always readable); the contact-suggestion popup anchors under the To row (to-row.height - 3px, identical 37px for single-line rows).
• src/mail.rs — parse_recipients also splits on \n (one-address-per-line pastes); parse_address rejects surviving control characters (\r, \n) so multiline input can never smuggle a header break into an address.
• src/compose_controller.rs — compose_recipient_query / complete_compose_recipient treat \n as a separator; completion after a newline-separated prefix normalizes to , instead of gluing onto the previous line.
• Tests added in both Rust files (separator splitting, control-char rejection, query/completion with newlines).

User-visible effects

Long To/Cc/Bcc lists wrap visibly and stay keyboard-navigable (arrows/Home/End across wrapped lines); Return still inserts a soft break inside the field, which now parses correctly at send. No change for short lists.

Tests

• New unit tests (see above); existing compose/mail suites cover the touched functions.
• Could not run the Rust gate or render the UI locally: this contribution was prepared on a host without the Rust toolchain (no cargo/rustc, no display), against byte-verified copies of main (all four base blobs hash-matched before patching). Relying on CI (cargo fmt --check, clippy, cargo test, slint-viewer --check) as the gate — please tell me if the row heights need adjustment after a visual check, and I will iterate.
• Follow-up noticed while here (out of scope): Cc/Bcc rows have no edited/suggestions-open wiring, so contact autocomplete only ever fires for To. Happy to file or fix separately.

Notes

• One logical change (issue Impossible to extend & navigate the "to" field when too many recipients (same with cc / bcc) #141), no new dependencies, no third-party material.
• Disclosure: prepared with AI assistance (Hermes agent). I reviewed every line of the diff and confirm it is my own contribution, submitted under AGPL-3.0-only, with no credentials, mailbox data, or personal fixture data included.