v0.151.0 — the Megosztás page stops reloading, and says how to connect

S-1: /sharing/status coerced idle->running on the PHASE channel, so the first
poll of every steady-state page load reported a terminal job that never ran and
the client's repaint-reload fired ~1.2s apart, forever. The coercion's real duty
(liveness must never be contradicted) belongs to the 'running' LEVEL field
beside it, and is now pinned by its own regression test.

S-4 core: a terminal 'running' is served exactly once, so a REAL bring-up cannot
re-arm the reload on the page it just caused. failed/needs_password/in-flight
are never consumed. Unified async-job feedback stays the ROADMAP item.

S-2/S-5: new connect card with the Windows form, the Mac form and the direct
smb://<IP>, read from the SAMBA container's netns (the controller is on a docker
bridge and would answer 172.x). Derived per render, cached nowhere - the address
is a DHCP lease. Underivable => the line is omitted.

sharing.html's <script> block is byte-identical to v0.150.0. Red-proofed three
ways. 23/23 packages green.

controller/internal/web/server.go

@@ -96,6 +96,10 @@ type Server struct {
 	storageInit storageInitState
 	// sambaEnsure is the Megosztás bring-up progress slot (v0.147.0, 4b) — same single-flight shape.
 	sambaEnsure sambaEnsureState
+	// sambaAddrFn is the connect-address seam (v0.151.0, S-2/S-5): the guest's LAN IPv4 for the
+	// „Csatlakozás a megosztáshoz" card, or "" when it cannot be read. nil → stackMgr.SambaLANAddress.
+	// Called PER RENDER and stored nowhere — the address is a DHCP lease (see sambaLANAddress).
+	sambaAddrFn func() string
 	netAgentFn func() (netAgent, error)
 	// fabUpload is the chunked browser .fab upload single-flight slot (v0.128.0).
 	fabUpload uploadState