feat: add projectile marker support for grenades and smokes

[fank]

Summary

• Thrown projectiles (grenades, smokes) are now exported as markers in the v1 JSON format
• Enables the web viewer to display grenade/smoke icons with trajectory positions
• Other projectiles (bullets, rockets) continue to use fire lines

Changes

• Add ProjectileEventToProjectileMarker converter that extracts icon filename from Arma path and creates marker with trajectory states
• Modify handleProjectileEvent to route thrown projectiles (Weapon="throw") to AddMarker instead of RecordFiredEvent
• Add tests for projectile marker conversion

Marker Format

The marker format follows web viewer expectations:

• Type: magIcons/<icon_filename>.paa
• Side: GLOBAL (-1)
• OwnerID: firer's OCAP ID
• Positions: trajectory from throw to impact

Example Output

[
  "magIcons/gear_smokegrenade_white_ca.paa",
  "Smoke Grenade (White)",
  243,
  -1,
  5,
  "FFFFFF",
  -1,
  [[243, [8345.61, 18302.5], 0, 1], [245, [8364.59, 18331.1], 0, 1]],
  [1, 1],
  "ICON",
  "Solid"
]

Test plan

• Unit tests for ProjectileEventToProjectileMarker pass
• Unit tests for empty icon fallback pass
• Full test suite passes
• Manual test with Arma 3 recording containing grenades/smokes

[github-actions]

Merging this branch changes the coverage (1 decrease, 1 increase)

Impacted Packages	Coverage Δ	🤖
github.com/OCAP2/extension/v5/internal/handlers	9.87% (ø)
github.com/OCAP2/extension/v5/internal/model/convert	89.92% (+4.21%)	👍
github.com/OCAP2/extension/v5/internal/model/core	0.00% (ø)
github.com/OCAP2/extension/v5/internal/storage/memory/export/v1	100.00% (ø)
github.com/OCAP2/extension/v5/internal/worker	15.54% (-0.32%)	👎

---

Coverage by file

Changed files (no unit tests)

Changed File	Coverage Δ	Total	Covered	Missed	🤖
github.com/OCAP2/extension/v5/internal/handlers/handlers.go	9.87% (ø)	770	76	694
github.com/OCAP2/extension/v5/internal/model/convert/convert.go	89.92% (+4.21%)	129 (+38)	116 (+38)	13	👍
github.com/OCAP2/extension/v5/internal/model/core/marker.go	0.00% (ø)	0	0	0
github.com/OCAP2/extension/v5/internal/storage/memory/export/v1/builder.go	100.00% (ø)	103 (+3)	103 (+3)	0
github.com/OCAP2/extension/v5/internal/worker/dispatch.go	17.50% (-0.45%)	200 (+5)	35	165 (+5)	👎

Please note that the "Total", "Covered", and "Missed" counts above refer to code statements instead of lines of code. The value in brackets refers to the test coverage of that file in the old version of the code.

Changed unit test files

• github.com/OCAP2/extension/v5/internal/model/convert/convert_test.go