feat: upload audio, get a private Swedish transcript, discuss it (#33, ADR-033) (#39)

Upload a recording (audio, or video with the camera off), get a private Swedish transcript, and chat about it.

- ADR-033: RLS-scoped private transcript store; ffprobe/ffmpeg intake; gateway transcription (iguana kb-whisper, berget fallback); in-process single-replica worker; chat over the transcript (local models only).
- ADR-034: optional two-engine mode (pianissimo + kb-whisper) reconciled by a LOCAL model; off unless TAPIR_RECONCILE_BASE_MODEL is set.
- ADR-035: real progress (phases, running/quiet/lost), phase logging, every judged spot stored, merged segments.
- Hardening from four adversarial reviews: errors logged and stored as kinds never text; per-engine deadlines; converted-length check; bounded queue; client hang-ups are not errors; strict local-alias check.
- Dockerfile: static ffmpeg/ffprobe 7.0.2 pinned by sha256 (#34). Built and inspected by hand; CI does not build the image on a PR, so its first CI build is this merge.

Uploads stay OFF until TAPIR_UPLOADS_ENABLED is set in the deployment.

Closes #33, #34, #42, #43, #44.

Co-authored-by: Mathias <mthbqv@gmail.com>

internal/config/uploads_local_test.go

@@ -0,0 +1,101 @@
+package config
+
+import (
+	"testing"
+	"time"
+)
+
+// What counts as a LOCAL model alias, and where that is demanded (ADR-034, ADR-035 review).
+// A private transcript may be sent to a local model and to nothing else; the check is a
+// guard against a misconfiguration or a crafted alias, so it must be strict about shape,
+// not just about a prefix.
+
+func TestIsLocalModel_AcceptsRealLocalAliasesAndNothingShapedLikeAnEscape(t *testing.T) {
+	tests := []struct {
+		alias string
+		want  bool
+	}{
+		{"koala/phi4-mini", true},
+		{"iguana/gemma4-26b", true},
+		{"iguana/gemma4-31b-think", true},
+		{"koala/qwen36-35b-a3b", true},
+		{"iguana/kb-whisper", true},
+		{"iguana/hf.co-model_v1:q4", true},
+		{"", false},
+		{"koala/", false},
+		{"iguana/", false},
+		{"gemma4-26b", false},
+		{"berget/mistral-small", false},
+		{"berget/koala/x", false},
+		{"xkoala/x", false},
+		{"Koala/x", false},
+		{" koala/x", false},
+		{"koala/x ", false},
+		{"koala/x y", false},
+		{"koala/x\n", false},
+		{"koala/../berget/kb", false},
+		{"koala//berget/mistral-small", false},
+		{"koala/x/y", false},
+		{"koala/x?host=berget", false},
+		{"koala/x#frag", false},
+		{"koala/x@evil", false},
+		{"koalа/x", false}, // Cyrillic а
+	}
+	for _, tt := range tests {
+		t.Run(tt.alias, func(t *testing.T) {
+			if got := IsLocalModel(tt.alias); got != tt.want {
+				t.Errorf("IsLocalModel(%q) = %v, want %v", tt.alias, got, tt.want)
+			}
+		})
+	}
+}
+
+func TestLoad_UploadChatModelMustBeLocalBecauseTheWholeTranscriptIsSentToIt(t *testing.T) {
+	for _, alias := range []string{"berget/mistral-small", "gemini/gemini-2.5-pro", "gemma4-26b", "koala/../berget/kb"} {
+		t.Run(alias, func(t *testing.T) {
+			clearUploadEnv(t)
+			setEnv(t, map[string]string{"TAPIR_UPLOAD_CHAT_MODEL": alias})
+
+			if _, err := Load(); err == nil {
+				t.Errorf("Load accepted TAPIR_UPLOAD_CHAT_MODEL=%q: a private transcript of up to 90,000 characters would be sent to it", alias)
+			}
+		})
+	}
+}
+
+func TestLoad_ALocalUploadChatModelIsAccepted(t *testing.T) {
+	clearUploadEnv(t)
+	setEnv(t, map[string]string{"TAPIR_UPLOAD_CHAT_MODEL": "iguana/gemma4-31b"})
+
+	cfg, err := Load()
+	if err != nil {
+		t.Fatalf("Load: %v", err)
+	}
+	if cfg.UploadChatModel != "iguana/gemma4-31b" {
+		t.Errorf("UploadChatModel = %q", cfg.UploadChatModel)
+	}
+}
+
+func TestLoad_TheEngineTimeoutDefaultsToTwentyMinutesAndMustBePositive(t *testing.T) {
+	clearUploadEnv(t)
+	cfg, err := Load()
+	if err != nil {
+		t.Fatalf("Load: %v", err)
+	}
+	if cfg.TranscribeEngineTimeout != 20*time.Minute {
+		t.Errorf("TranscribeEngineTimeout = %v, want 20m: a 90-minute recording takes about 8 minutes on kb-whisper, and two wedged engines in sequence must leave the job time to reach a fallback", cfg.TranscribeEngineTimeout)
+	}
+
+	setEnv(t, map[string]string{"TAPIR_TRANSCRIBE_ENGINE_TIMEOUT": "7m"})
+	cfg, err = Load()
+	if err != nil || cfg.TranscribeEngineTimeout != 7*time.Minute {
+		t.Errorf("override: %v, %v", cfg.TranscribeEngineTimeout, err)
+	}
+
+	for _, bad := range []string{"0", "-1m", "soon"} {
+		setEnv(t, map[string]string{"TAPIR_TRANSCRIBE_ENGINE_TIMEOUT": bad})
+		if _, err := Load(); err == nil {
+			t.Errorf("Load accepted TAPIR_TRANSCRIBE_ENGINE_TIMEOUT=%q", bad)
+		}
+	}
+}