fix: recover add-node coverage after profile changes

[anthony-at-pieces]

Summary

• let the Add Node sheet request target-area node data when coverage is missing
• deduplicate in-flight recovery requests while allowing retries after cache invalidation or an uncovered response
• use the current enabled profiles and upload mode for the targeted, user-initiated request

Test plan

• flutter test test/widgets/add_node_sheet_coverage_recovery_test.dart
• flutter analyze --no-fatal-infos
• flutter test

Closes #185

[stopflock]

Were you able to reproduce 185? I can't. Any change to the list of enabled profiles should trigger a cache clear and re-fetch already.

[anthony-at-pieces]

Not on a device - I don't have ios - but I reproduced it in a widget test so I could verify red/green -

you are right, the profile change triggers a cache clear and refetch at the map/cache layer,

but the bug was in the sheet's own request dedupe - after one successful area request - the sheet suppressed re-requesting even after it's cached coverage was invalid underneath. So the re-fetch never reached the sheet's target area while it sat open. my bad I should have been more explicit in that - with that information, you might be able to recreate?

the "widget" test is checked in on this PR.