fix: send-reminder cron

Makefile

@@ -6,10 +6,13 @@ USER        := $(shell id -un)
 PORT        ?= 8000
 SERVICE     := osiris
 UNIT_FILE   := /etc/systemd/system/$(SERVICE).service
-REMINDER_SH := $(PROJECT_DIR)/deploy/send-reminders.sh
 CRON_SCHED  ?= * * * * *
 CRON_LOG    ?= $(PROJECT_DIR)/reminders.log
 MANAGE      := $(UV) run python manage.py
+# The reminder job as one line: cron's environment is nearly empty, so uv is
+# called by absolute path and loads .env (VAPID keys) itself via --env-file.
+# --no-sync: don't resolve dependencies (needs network) on a cron tick.
+REMINDER_CMD := cd $(PROJECT_DIR) && $(UV) run --no-sync --env-file .env python manage.py send_reminders
 
 .PHONY: help
 help: ## Show this help
@@ -88,24 +91,23 @@ service-uninstall: ## Stop and remove the systemd service
 
 # --- cron ------------------------------------------------------------------
 
-# The script path is the marker: it identifies our line without needing a literal
-# '#' comment, which make would strip as a comment of its own.
+# 'send[-_]reminders' is the marker identifying our line, so reinstalling stays
+# idempotent and also cleans up entries from the old wrapper-script era.
 .PHONY: cron
-cron: ## Install the reminder cron job (every 10 minutes, idempotent)
-	@chmod +x $(REMINDER_SH)
-	@( crontab -l 2>/dev/null | grep -vF '$(REMINDER_SH)' ; \
-	   echo "$(CRON_SCHED) $(REMINDER_SH) >> $(CRON_LOG) 2>&1" ) | crontab -
+cron: ## Install the reminder cron job (idempotent)
+	@( crontab -l 2>/dev/null | grep -vE 'send[-_]reminders' ; \
+	   echo "$(CRON_SCHED) $(REMINDER_CMD) >> $(CRON_LOG) 2>&1" ) | crontab -
 	@echo "Installed:"
-	@crontab -l | grep -F '$(REMINDER_SH)'
+	@crontab -l | grep -F 'send_reminders'
 
 .PHONY: cron-remove
 cron-remove: ## Remove the reminder cron job
-	@crontab -l 2>/dev/null | grep -vF '$(REMINDER_SH)' | crontab -
+	@crontab -l 2>/dev/null | grep -vE 'send[-_]reminders' | crontab -
 	@echo "Removed."
 
 .PHONY: cron-test
 cron-test: ## Run the reminder job once, reporting what it would send
-	$(REMINDER_SH) --dry-run
+	@$(REMINDER_CMD) --dry-run
 
 # --- Frontend --------------------------------------------------------------