Add a small, tested base for all three clients, and Gitea CI/release workflows

internal/client (new): a typed Go HTTP client for the API - login,
register, logout, me, and full CRUD for games/platforms - shared by the
TUI and the Fyne GUI so request-building, auth and error handling (an
APIError with the HTTP status) live in one tested place instead of being
duplicated. 8 tests against an httptest server covering success, 401, 403
and that the token is stored/cleared at the right times.

cmd/tui (rewrite): drops the old unauthenticated read-only viewer. Now a
login screen (bubbles/textinput) -> a scrollable games table
(bubbles/table) with 'r' to refresh, built as an explicit state machine
(screenLogin/screenLoading/screenGames) so Update's transitions are
testable without a real terminal. 9 tests driving Update() directly.

cmd/gui (rewrite): drops raylib for Fyne. Same shape as the TUI - a login
form, then a games table, with networking on a goroutine and fyne.Do for
the UI updates. The table-cell and login-validation logic are plain
functions with no Fyne/display dependency, so they're tested directly (7
tests) rather than needing Fyne's headless test driver.

internal/api: tagged every operation (Auth/Platforms/Games/Misc) so the
generated OpenAPI spec groups into named services instead of one bucket;
api/openapi.json regenerated. Added CORS middleware (wildcard origin, no
credentials needed since clients use a bearer token, not the cookie) -
needed for the new web client's browser requests to the API's a different
origin.

web/ (new): an Angular 22 + Material app, API client generated from
api/openapi.json via ng-openapi-gen (services: true for per-resource
classes - AuthService/GamesService/PlatformsService - instead of one
generic Api facade). A Session service holds the token/user as signals,
persists the token to localStorage, and is the only thing that calls the
generated AuthService; an HttpInterceptorFn attaches the bearer token to
every request; a CanActivateFn guard protects /games. Login and Games are
standalone, lazy-loaded route components. 21 tests (Vitest, Angular's new
default - no browser/Karma needed) covering the service, interceptor,
guard and both components, run via `npm test` exactly as CI will call it.

Justfile: fixed run-tui/run-gui, which used `go run .../main.go` - broken
now that both packages span multiple files, since that only compiles the
one named file. Added web-install/web-dev/web-build/web-test.

.gitea/workflows/ci.yml (moved from .github, which Gitea doesn't read):
on push to main/develop - gofmt, go vet, go build, go test, go mod tidy
diff (with the Fyne build's system deps installed), sqlc diff, and the
web app's build+test.

.gitea/workflows/release.yml (new): on a vX.Y.Z tag, cross-compiles
api+tui for linux/darwin/windows (amd64+arm64, pure Go, no cgo), builds
the Fyne GUI for linux/amd64 only (cgo + its OpenGL/X11 link means it
can't cross-compile from one Linux runner the way api/tui do, and this
repo has no registered macOS/Windows runner to build it on natively -
documented in the workflow's comments), builds the web app, and creates a
Gitea release with all of it attached via the Gitea API. Written to
Gitea's documented GitHub-Actions-compatible syntax but not executable
from here - there's no Gitea server in this environment to run it
against, unlike everything else in this commit, which was.

Verified: every Go package builds/vets/tests clean; sqlc diff and go mod
tidy -diff are clean; the Angular app builds for production and its test
suite passes via `npm test`/`npm run build` (the exact commands CI runs),
including after a clean `npm ci` from the committed lockfile; the new CORS
config was checked with real preflight and GET requests against a running
server, not just read.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

cmd/gui/table_test.go

@@ -0,0 +1,59 @@
+package main
+
+import (
+	"testing"
+
+	"completed/internal/model"
+)
+
+func TestGameTableSize(t *testing.T) {
+	games := []model.Game{{Name: "Doom"}, {Name: "Half-Life"}}
+
+	rows, cols := gameTableSize(games)
+	if rows != 3 {
+		t.Errorf("rows = %d, want 3 (header + 2 games)", rows)
+	}
+	if cols != len(gameColumns) {
+		t.Errorf("cols = %d, want %d", cols, len(gameColumns))
+	}
+}
+
+func TestGameTableSizeEmpty(t *testing.T) {
+	rows, _ := gameTableSize(nil)
+	if rows != 1 {
+		t.Errorf("rows = %d, want 1 (header only)", rows)
+	}
+}
+
+func TestGameCellTextHeader(t *testing.T) {
+	for col, want := range gameColumns {
+		if got := gameCellText(nil, 0, col); got != want {
+			t.Errorf("gameCellText(nil, 0, %d) = %q, want %q", col, got, want)
+		}
+	}
+}
+
+func TestGameCellTextDataRows(t *testing.T) {
+	games := []model.Game{
+		{Name: "Doom", PlatformName: "PC", Score: 95, ReleaseDate: "1993-12-10"},
+		{Name: "Half-Life", PlatformName: "PC", Score: 96, ReleaseDate: "1998-11-19", Finished: "1999-01-01"},
+	}
+
+	tests := []struct {
+		row, col int
+		want     string
+	}{
+		{1, 0, "Doom"},
+		{1, 1, "PC"},
+		{1, 2, "95"},
+		{1, 3, "1993-12-10"},
+		{1, 4, ""},
+		{2, 0, "Half-Life"},
+		{2, 4, "✓"},
+	}
+	for _, tt := range tests {
+		if got := gameCellText(games, tt.row, tt.col); got != tt.want {
+			t.Errorf("gameCellText(games, %d, %d) = %q, want %q", tt.row, tt.col, got, tt.want)
+		}
+	}
+}