feat: bloom release workflow + bridge exec_depend

[rafal-gorecki]

Summary

Wire up apt-installable distribution of `rosbot_ros` packages via bloom, plus declare the MAVLink bridge as a rosdep dependency.

• New release workflow (`.github/workflows/release.yaml`) — manually-dispatched. Bumps every first-party `package.xml` to a shared version (plain numeric, matches existing `1.0.0` / `0.18.8` tag history), tags, then runs `bloom-release` per package against `husarion/rosbot_ros-release`. Pre-release dispatches (`pre_release=true`) tag `.pre.N` and skip bloom so they don't ship to rosdistro.
• rosbot_bringup — adds `<exec_depend>rosbot_mavlink_bridge</exec_depend>`. `mavlink.launch.py` already uses the bridge by name; rosdep will pull it from apt once the bridge lands in rosdistro (paired PR feat: prepare bridge for bloom release to rosdistro rosbot-firmware#8).

After this PR + the firmware PR + bloom one-shot setup, users on apt will `apt install ros-jazzy-rosbot-bringup` and get bridge + everything else automatically — no more `vcs import` for production.

Sensitive spots

• Tag scheme: plain numeric (no `v` prefix) chosen to match existing tag history (`1.0.0`, `0.18.8`). `bloom-release --new-track` for each of 10 packages must use `:{version}` release-tag pattern.
• Sibling repos (`husarion_components_description`, `husarion_controllers`, `tf_namespace_bridge`, `micro-ROS-Agent`) are NOT in this release — they ship from their own source repos. The `PACKAGES` env in the workflow is the explicit allow-list.
• First bloom-release per distro requires `--new-track` interactively, then merge of the initial rosdistro PR by upstream maintainers. Subsequent releases are CI-only.

One-shot setup needed before bloom job runs green

1. Create empty `husarion/rosbot_ros-release` repo.
2. Add it + `husarion/rosdistro` (fork) to the `HUSARION_BOT` App installation.
3. Locally at a release tag, loop over the 10 packages and run `bloom-release --new-track --rosdistro jazzy --track jazzy --release-repo-url git@github.com:husarion/rosbot_ros-release.git $pkg`. Release tag pattern: `:{version}` (no `v` prefix).
4. Re-run the workflow; subsequent releases reuse the tracks.

Full checklist also lives in the `bloom-release` job header.

Test plan

• `pre-commit run` on staged — green
• YAML syntax check on `release.yaml`
• `prettier-package-xml` + `sort-package-xml` accept the new `exec_depend`
• Will validate on actual workflow dispatch after one-shot setup is in place