fix(doc): point the ADR-0010 doc link at GitHub, not the mdbook source tree

docs/adr/ lives outside doc/src/, so a relative mdbook link can't reach it
(mdbook-linkcheck: "File not found: ../../adr/0010-mission-lifecycle-contract.md").
Every other page cross-referencing docs/adr/ already uses a full GitHub URL for
the same reason.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GJ9YSNzdp9HxP6j7SjEkCR
Signed-off-by: David Bensoussan <d.bensoussan@proton.me>

Author: Minipada

doc/src/dc/measurements/mission_nav2.md

@@ -4,7 +4,8 @@
 
 The nav2 adapter of the Mission Measurement for nav2's `NavigateToPose` action -- a single-pose
 navigation goal, the base case the mission lifecycle contract (#305, recorded in
-[ADR-0010](../../adr/0010-mission-lifecycle-contract.md)) was agreed against. Emits a
+[ADR-0010](https://github.com/minipada/ros2_data_collection/tree/jazzy/docs/adr/0010-mission-lifecycle-contract.md))
+was agreed against. Emits a
 `mission_start` Record when a goal is accepted and a `mission_end` Record once it reaches a
 terminal state. `NavigateThroughPoses` and `FollowWaypoints` are its siblings (#388/#389): same
 Record schema, same `mission_id`/`sequence` conventions, each with its own `mission_type`.