chore: add go.sum to version control and copy in Dockerfile

Add empty go.sum file (no external dependencies yet) and update the
Dockerfile build stage to COPY go.sum alongside go.mod for reproducible
module downloads. This ensures the Docker build does not fail when Go
requires go.sum to be present.

Closes leeworks-agents/gitea-mobile#203
Closes leeworks-agents/gitea-mobile#180

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Dockerfile

@@ -1,7 +1,7 @@
 # Stage 1: Build
 FROM golang:1.22-alpine AS builder
 WORKDIR /app
-COPY go.mod ./
+COPY go.mod go.sum ./
 RUN go mod download
 COPY . .
 RUN CGO_ENABLED=0 GOOS=linux go build -ldflags="-s -w" -o /gitea-mobile ./cmd/server

SMOKE_TEST.md

@@ -73,9 +73,9 @@ curl -s https://gitea-mobile.testing.leeworks.dev | head -5
 3. Tap on a PR to see details
 4. **Expected**: PR diff summary or review status displays correctly
 
-## Step 7: Core Functionality -- Triage Queue
+## Step 7: Core Functionality -- Dashboard / Triage Queue
 
-1. Navigate to the Triage tab (`/triage`)
+1. Navigate to the Dashboard/Triage tab (`/`)
 2. **Expected**: Unassigned issues and PRs awaiting review appear sorted by priority
 
 ## Step 8: Create Issue (Write Operation)
@@ -116,7 +116,7 @@ curl -s https://gitea-mobile.testing.leeworks.dev | head -5
 | 4 | Auth | Token saved, API calls work |
 | 5 | Issues | List loads, filter works |
 | 6 | PRs | List loads with review status |
-| 7 | Triage | Queue displays correctly |
+| 7 | Dashboard/Triage | Queue displays correctly at `/` |
 | 8 | Create issue | Issue created in Gitea |
 | 9 | Apply label | Label applied via API |
 | 10 | PWA | Standalone mode, safe areas, dark mode |