Drop Completed Steps from TODO.md; the tracker is the record (closes #112)

Every issue branch added an entry to the same list, so each branch
conflicted with `next` as soon as another one landed. The tracker already
records what is done, in more detail than the list did.

The Workflow section now says the tracker is that record, in place of the
rule that issue branches leave this file alone. Status points to the 1.0.0
milestone for what is open, and Next Step says @sneak tags `v1.0.0` after
running webhooker in limited production. In Future Steps, each item that
overlaps with what webhooker already does now says what exists and what is
still missing, and the delivery status and retry UI item is gone because the
event log, replay and resubmit cover it.

Model: opus-5-5

TODO.md

@@ -37,15 +37,22 @@ is kept mergeable at all times, which is the point of the branch.
 - Per-webhook rate limits, set in the web UI and enforced in the receiver
   handler, on top of the receiver's existing limits, which `RECEIVER_RATE_LIMIT`
   sets for the whole server (see Rate Limiting in the README)
-- API key authentication for programmatic access (APIKey model exists; Bearer
-  token middleware does not)
+- API key authentication for programmatic access (the `APIKey` model exists, but
+  nothing creates a key and no middleware checks one)
 - REST API v1
     - CRUD for webhooks, entrypoints, targets
     - event viewing and filtering endpoints
     - event redelivery endpoint
     - OpenAPI specification
-- Analytics dashboard: success rates, response times, volume
-- A remember-me option at login
+- Analytics in the web UI: response times summarised per webhook or per target,
+  and figures for all webhooks together. The webhook page already shows event,
+  delivery and failure counts and failure percentages, the target list counts
+  each target's deliveries, the event log and each event's page show every
+  attempt's duration, and `/metrics` carries server-wide counts and delivery
+  durations
+- A remember-me option at login. Every session already survives a browser
+  restart: it lasts up to 7 days, and ends sooner after `SESSION_IDLE_TIMEOUT`
+  (default 24 hours) without activity
 - Password reset flow for a forgotten password over the web. The authenticated
   password _change_ flow already landed, and a lost password is recoverable from
   the console with `webhooker resetpw`
@@ -55,7 +62,11 @@ is kept mergeable at all times, which is the point of the branch.
     - SNS and S3 delivery targets
     - data transformations (e.g. a configurable Slack message format; the Slack
       target sends one fixed format today)
-    - JSONL file delivery with periodic S3 upload
+    - JSONL file delivery with periodic S3 upload (the `database` target already
+      archives events to SQLite files, rotated hourly, daily or monthly if set,
+      and the webhook page offers them as one gzipped JSON download)
     - webhook event search, and filtering beyond the event log's failed and
       pending views
-    - multi-user with role-based access control
+    - multi-user with role-based access control (each webhook already belongs to
+      one account, but there is only the account made at first boot and no way
+      to add another)