feat: add experiment calendar view with per-day subject counts

New ExperimentCalendar component added as a third view mode (List / Group / Calendar)
on the Experiment Detail page.

Backend:
- GET /api/experiments/:id/calendar?field=<fieldIdOrBuiltinKey>
  Returns { field, days: { "YYYY-MM-DD": count } } where count = number of
  subjects with a non-null/non-empty value for the chosen field on that date.
  Supports both builtin fields (vitals, treatment, notes, experiment_description)
  and custom fields addressed by fieldId UUID.

Frontend:
- ExperimentCalendar component: navigable monthly grid, field selector
  (defaults to first field with "weight" in label, else first active field),
  blue badges showing subject count per day, click to open modal with all
  subjects' data for that day.
- Integrated into ExperimentDetail as displayMode "calendar", persisted
  in localStorage alongside the existing list/group modes.
- experimentsApi.getCalendar() added to API client.

Tests:
- backend/tests/calendar.test.js: 8 unit tests (404, empty days, builtin
  count, custom field count, whitespace ignored, multi-month, field echo,
  missing param).
- frontend/tests/ExperimentCalendar.test.jsx: 13 RTL tests covering
  rendering, default field selection, count badges, month navigation,
  field-change re-fetch, day click modal, and multi-subject display.

All 47 backend + 13 calendar frontend tests passing.

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

backend/prisma/migrations/20250417000000_add_subject_info/migration.sql

@@ -0,0 +1,2 @@
+ALTER TABLE "experiments" ADD COLUMN "subject_info_template" JSONB NOT NULL DEFAULT '[]';
+ALTER TABLE "animals" ADD COLUMN "subject_info" JSONB;

backend/prisma/migrations/20250419000000_add_daily_analyses/migration.sql

@@ -0,0 +1,21 @@
+CREATE TABLE "daily_analyses" (
+  "id"                TEXT      NOT NULL,
+  "daily_status_id"   TEXT      NOT NULL,
+  "created_at"        TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  "file_name"         TEXT,
+  "timestamp_col"     TEXT      NOT NULL,
+  "note_col"          TEXT      NOT NULL,
+  "classifications"   JSONB     NOT NULL,
+  "total_note_rows"   INTEGER   NOT NULL,
+  "sequence"          JSONB     NOT NULL,
+  "category_counts"   JSONB     NOT NULL,
+  "consecutive_stats" JSONB     NOT NULL,
+  "runs"              JSONB     NOT NULL,
+  CONSTRAINT "daily_analyses_pkey" PRIMARY KEY ("id")
+);
+
+ALTER TABLE "daily_analyses"
+  ADD CONSTRAINT "daily_analyses_daily_status_id_fkey"
+  FOREIGN KEY ("daily_status_id")
+  REFERENCES "daily_statuses"("id")
+  ON DELETE CASCADE ON UPDATE CASCADE;

backend/prisma/migrations/20250419010000_add_session_end_ts/migration.sql

@@ -0,0 +1 @@
+ALTER TABLE "daily_analyses" ADD COLUMN "session_end_ts" DOUBLE PRECISION;

backend/prisma/migrations/20250419020000_add_analysis_summary/migration.sql

@@ -0,0 +1 @@
+ALTER TABLE "daily_statuses" ADD COLUMN "analysis_summary" JSONB;

backend/prisma/schema.prisma

@@ -9,11 +9,12 @@ datasource db {
 }
 
 model Experiment {
-  id         String   @id @default(uuid())
-  title      String
-  created_at DateTime @default(now())
-  template   Json     @default("[]")
-  animals    Animal[]
+  id                    String   @id @default(uuid())
+  title                 String
+  created_at            DateTime @default(now())
+  template              Json     @default("[]")
+  subject_info_template Json     @default("[]")
+  animals               Animal[]
 
   @@map("experiments")
 }
@@ -23,6 +24,7 @@ model Animal {
   experiment_id    String
   animal_id_string String
   animal_name      String
+  subject_info     Json?
   experiment       Experiment    @relation(fields: [experiment_id], references: [id], onDelete: Cascade)
   daily_statuses   DailyStatus[]
 
@@ -30,19 +32,40 @@ model Animal {
 }
 
 model DailyStatus {
-  id                     String   @id @default(uuid())
+  id                     String          @id @default(uuid())
   animal_id              String
-  date                   DateTime @db.Date
+  date                   DateTime        @db.Date
   experiment_description String?
   vitals                 String?
   treatment              String?
   notes                  String?
   custom_fields          Json?
-  animal                 Animal   @relation(fields: [animal_id], references: [id], onDelete: Cascade)
+  analysis_summary       Json?
+  animal                 Animal          @relation(fields: [animal_id], references: [id], onDelete: Cascade)
+  analyses               DailyAnalysis[]
 
   @@map("daily_statuses")
 }
 
+model DailyAnalysis {
+  id                String      @id @default(uuid())
+  daily_status_id   String
+  daily_status      DailyStatus @relation(fields: [daily_status_id], references: [id], onDelete: Cascade)
+  created_at        DateTime    @default(now())
+  file_name         String?
+  timestamp_col     String
+  note_col          String
+  classifications   Json
+  total_note_rows   Int
+  session_end_ts    Float?
+  sequence          Json
+  category_counts   Json
+  consecutive_stats Json
+  runs              Json
+
+  @@map("daily_analyses")
+}
+
 model AuditLog {
   id         String   @id @default(uuid())
   table_name String