Add custom aircraft encyclopedia feature (#707)

## Summary

Adds a `--aircraft-file` option (`aircraft-file` config key) that lets
server admins extend or override SkyEye's built-in aircraft encyclopedia
with a user-supplied YAML file. This makes community aircraft mods that
SkyEye does not recognize work correctly — they can be categorized,
threat-assessed, named on the radio, and matched to compatible tankers.

Modeled on the existing custom locations feature.

## How it works

- New `pkg/encyclopedia/custom.go`: an unexported `serializedAircraft`
schema parses directly into `encyclopedia.Aircraft`.
`LoadCustomAircraft` reads YAML (a superset of JSON, so `.json` files
also work), and `AddCustomAircraft` registers entries into the lookup
table.
- Validation: required `acmi_short_name`, at least one reporting-name
field
(`nato_reporting_name`/`nickname`/`official_name`/`platform_designation`),
exactly one wing tag, and recognized tag/fuel values.
- Wiring: `--aircraft-file` flag in `cmd/skyeye`, `CustomAircraft` field
in `conf.Configuration`, and registration in
`application.NewApplication` just before the radar (its first consumer)
is built.
- Overrides: an entry reusing a built-in ACMI short name replaces it,
logged at INFO. Each loaded aircraft logs one INFO line.

## Docs

`docs/AIRCRAFT.md` documents the schema, tags, threat radius, refueling,
and how to find the ACMI short name, using the A-4 Skyhawk as a worked
example. Cross-linked from `docs/ADMIN.md`.

## Testing

- `make test` — passes, including new `pkg/encyclopedia/custom_test.go`
(YAML/JSON parsing, validation errors, tag/fuel mapping, override
behavior).
- `make lint vet fix format` — clean.
- `make skyeye` — builds.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

Update replacements through June 2026

Fix crash loop when ACMI stream sends zero ReferenceTime

DCS2ACMI sends ReferenceTime=0001-01-01T00:00:00Z as a base epoch,
encoding actual mission time as a large offset. This date is also
Go's zero time.Time, so the IsZero() guard that detects "reference
time not yet received" fired on every time frame, causing an infinite
reconnect loop against Lima Kilo.

Replace the IsZero() check with a dedicated referenceTimeSet bool.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Pass location names to recognizer initial prompt (#694)

## Summary

- Adds a `WithLocations` functional option to `NewWhisperRecognizer` and
the OpenAI recognizers
- When set, location names are appended to Whisper's initial prompt so
the model biases transcription towards known place names
- The application wires this up automatically from `config.Locations`

Fixes #692: Whisper was transcribing location names as phonetic
near-misses (e.g. "Incirlik" → "INSULIC"). Including the configured
location names in the initial prompt is sufficient to correct
transcription.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Opus 4.7 <noreply@anthropic.com>

Clean up VECTOR implementation (#687)

Fix dependency scanner findings (#648)

## Summary
- Update `google.golang.org/grpc` from v1.75.0 to v1.79.3 to fix
authorization bypass vulnerability (Dependabot alert #10)
- Add top-level `permissions: {}` to CI workflow to deny all permissions
by default
- Add `permissions: { contents: read }` to all jobs that only need
checkout access (lint, test, build-*, release)

## Test plan
- [ ] CI passes (lint, vet, test, build)
- [ ] Dependabot alert #10 auto-closes after merge
- [ ] Code scanning alerts #2-8 clear after merge

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Fix linter error

Update Siri voice docs for macOS 26

Add STROBE command

Update golangci-lint