Use configured timezone throughout codebase

- Add config/timezone.go with timezone utilities:
  - SetDisplayTimezone(), GetDisplayTimezone()
  - Now(), Today() - current time/date in display TZ
  - ParseDateInDisplayTZ(), ToDisplayTZ() - parsing helpers

- Initialize timezone at startup in main.go

- Update all datetime logic to use configured timezone:
  - handlers/handlers.go - all time.Now() calls
  - handlers/timeline.go - date parsing
  - handlers/timeline_logic.go - now calculation
  - models/atom.go - ComputeUIFields()
  - models/timeline.go - ComputeDaySection()
  - api/plantoeat.go - meal date parsing
  - api/todoist.go - due date parsing
  - api/trello.go - due date parsing

This ensures all dates/times display correctly regardless
of server timezone setting.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

1 files changed, 47 insertions, 0 deletions

diff --git a/IMPLEMENTOR.md b/IMPLEMENTOR.md
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+# Implementation Plan: Timeline Feature
+
+## Phase 1: Database Layer (Store)
+**Goal:** Enable fetching data by date range.
+
+1.  **Update Interface:** Modify `internal/store/store.go` to add:
+    *   `GetTasksByDateRange(start, end time.Time) ([]models.Task, error)`
+    *   `GetMealsByDateRange(start, end time.Time) ([]models.Meal, error)`
+    *   `GetCardsByDateRange(start, end time.Time) ([]models.Card, error)`
+2.  **Update Implementation:** Modify `internal/store/sqlite.go` to implement these methods using SQL queries.
+3.  **Test:** Create/Update `internal/store/store_test.go` to verify the queries work correctly.
+
+## Phase 2: Core Logic & Models
+**Goal:** Aggregate and normalize data into a timeline structure.
+
+1.  **Create Models:** Create `internal/models/timeline.go` with `TimelineItem` and `TimelineItemType`.
+2.  **Create Logic:** Create `internal/handlers/timeline_logic.go`.
+    *   Implement `BuildTimeline(store Store, calendarClient *api.GoogleCalendarClient, start, end time.Time)`.
+    *   **Logic:**
+        *   Fetch Tasks, Meals, Cards from Store.
+        *   Fetch Events from Calendar Client.
+        *   Convert all to `TimelineItem`.
+        *   **Apply Meal Defaults:**
+            *   If `MealType` == "breakfast" -> Set time to 08:00
+            *   If `MealType` == "lunch" -> Set time to 12:00
+            *   If `MealType` == "dinner" -> Set time to 19:00
+            *   Else -> Set time to 12:00
+        *   Sort items by `Time`.
+3.  **Test:** Create `internal/handlers/timeline_logic_test.go` to test merging and sorting (TDD).
+
+## Phase 3: HTTP Handler & Routing
+**Goal:** Expose the timeline via HTTP.
+
+1.  **Create Handler:** Create `internal/handlers/timeline.go`.
+    *   Inject `Store` and `GoogleCalendarClient`.
+    *   Parse query params (`start`, `days`).
+    *   Call `BuildTimeline`.
+    *   Render template.
+2.  **Register Route:** Update `cmd/dashboard/main.go` to map `/timeline` to the new handler.
+
+## Phase 4: UI
+**Goal:** Visualize the timeline.
+
+1.  **Create Template:** Create `web/templates/partials/timeline-tab.html`.
+    *   Iterate over items grouped by day.
+    *   Show time, icon, title, and details.
+2.  **Update Main View:** Update `web/templates/index.html` to add the "Timeline" tab and HTMX trigger.