inbound-antispam-panel: filter lists, written as rspamd maps

Step 5/12 of docs/plans/inbound-antispam-panel.md.

Store: AddSpamListEntry, ListSpamListEntries, DeleteSpamListEntry.
internal/inbound/lists.go validates and normalises an entry - sender
address, sender domain, client address or network (canonical text, an
IPv4-mapped address as IPv4, /0 refused) - and writes the lists as six
map files under /data/antispam (ANTISPAM_DIR), each atomically, 0644 in
a 0755 directory: the filter is another user in another container. All
six are written on every change and on every start with the relay on,
empty ones included. An entry whose maps could not be written is taken
back out of the table. The writer refuses a stored value with
whitespace, a newline or # in it.

The plan's allow.map / deny.map became one file per list and entry
type: to rspamd an IP map and a sender map are different map types.

deploy/antispam/rspamd/multimap.conf holds the rules; the fragment
mounts it and ./data/antispam into the sidecar. Deny is a prefilter
reject, allow a symbol weighing -100. Tried in a throwaway rspamd 3.11
container on the test server:
  - with allow as a prefilter accept, an address on both lists was
    accepted and an IP on both was refused - the rule that ran first
    decided; with the weight, deny won in all five mixed cases;
  - IPv4, IPv6, address (any case), domain (not its subdomains) match;
  - a rewritten file is reread in about ten seconds, no restart;
  - files that appear after rspamd started are loaded the same way.

No page edits the lists yet (step 6).

Checked on the test server, uncommitted tree: go vet ./... ok,
go test ./... ok (22 packages), make e2e ok - with the relay on
/data/antispam is 755 and holds the six maps, 644, empty.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/plans/inbound-antispam-panel.md

@@ -102,13 +102,13 @@ Mirror send-log retention:
 | Entry types | sender address, sender domain (`@domain` suffix), client IP / CIDR |
 | Precedence | **deny overrides allow** |
 | Scope | instance-wide (not per inbound domain in v1) |
-| Where applied | **rspamd map files** under `/data/antispam/` (allow.map, deny.map); documented compose fragment mounts them into the sidecar |
+| Where applied | **rspamd map files** under `/data/antispam/`, one per list and entry type (`allow_ip.map`, `allow_from.map`, `allow_domain.map`, `deny_…`) - an IP map and a sender map are different map types to rspamd; documented compose fragment mounts them into the sidecar. Deny is a prefilter reject, allow a weight of -100 (as built: two prefilters do not give "deny overrides allow") |
 | SelfPost pre-check | **out of v1** — lists live in rspamd only |
 | Edit access | global administrator only |
 | When inactive | lists editable in the panel but UI warns that sync applies only when `INBOUND_ANTISPAM_MILTER` is set; `postfix reload` / rspamd reload documented in guide |
 
-List change → atomic map rewrite (same pattern as Postfix maps) → rspamd reload
-via documented operator step or sidecar `SIGHUP` in the compose fragment.
+List change → atomic map rewrite (same pattern as Postfix maps). No reload:
+rspamd rereads a changed map file by itself (about ten seconds on 3.11).
 
 ### Activation
 
@@ -247,7 +247,7 @@ Target version cut: **`2.1.0`** (MINOR), after `2.0.0`. One commit per step;
 - [x] Migration `0002_inbound_spam_log.sql` on the 2.0 baseline — **Composer**
 - [x] Inbound journal-milter + Postfix wiring — **Composer**
 - [x] mail.log tailer: inbound reject rows — **Composer**
-- [ ] List CRUD + validation + atomic rspamd map sync — **Composer**
+- [x] List CRUD + validation + atomic rspamd map sync — **Composer**
 - [ ] Panel: Inbound › Log and Inbound › Filter lists from the kit partials, mockups `in-log` / `in-filter-lists` (add client IP and engine columns mockup-first), evidence pairs — **Composer**
 - [ ] Backup includes `/data/antispam/` — **Composer**
 - [ ] Unit + handler tests — **Composer**