feat(runtime): add portable runtime support

req: push/009 req: push/010 req: push/011

AGENTS.md

@@ -61,7 +61,7 @@ Keep it stable. Prefer pointers to canonical sources over copied structure, file
 - Routing, auth, sessions, transport, transitions, sync, async data helpers, multipart parsing/uploads, and storage belong in integration/user crates; hemx-axum preserves normal HTTP auth, credentials, CSRF, multipart/browser fallback, and progressive-enhancement semantics rather than defining policy in core. Sync is optional integration state reconciliation over push/transport, not core. req: auth/001 req: auth/002 req: auth/003 req: auth/004 req: auth/005 req: async_data/001 req: async_data/002 req: async_data/003 req: multipart/001 req: multipart/002 req: multipart/003 req: sync/001 req: sync/008
 - The SaaS production reference must use real links/URLs for navigation and an ongoing server-owned canonical SSE stream; bounded one-event behavior is a test probe, not the public transport contract. Browser history restores saved generated page snapshots and scroll position when available, with partial-fetch fallback, and restored revealed bindings must re-arm. req: nav/001 req: nav/002 req: nav/005 req: convention/014 req: push/003 req: examples/014
 - Public examples and beginner APIs should use templates plus Rust, generated component APIs, resources, view wrappers, render/page helpers, `#[hemx::app]`, plain `#[hemx::handler]` functions, and `IntoEffect`, not atoms, raw ids, selectors, wire formats, runtime opcodes, manual registries, `$OUT_DIR` includes, raw render/lower calls, raw HTML construction, imperative DOM mutation, or raw effect constructors; keep advanced layers out of starters. req: canonical_authoring/001 req: canonical_authoring/004 req: canonical_authoring/006 req: canonical_authoring/010 req: canonical_authoring/015 req: invariant/003 req: dx/001 req: dx/002 req: dx/010 req: component/003 req: component/004 req: component/005 req: view/001 req: view/002 req: view/003 req: html_safety/001 req: html_safety/003 req: html_safety/005 req: public_api/001 req: public_api/002 req: public_api/003 req: public_api/005 req: public_api/006 req: progressive_disclosure/001 req: progressive_disclosure/002 req: progressive_disclosure/003 req: derive_app/001 req: derive_app/002 req: derive_handler/001 req: derive_handler/002 req: derive_handler/003 req: derive_handler/004 req: derive_handler/005
-- Typed partial swaps should stay expressed as generated target plus rendered partial plus swap kind, not selector-driven rerendering or response-side selector retargeting; HTTP, page navigation, push, and island behavior adapt around that loop, and docs should layer new primitives progressively. Navigation is an effect/page-swap concern, not a core router framework; enhanced links and GET forms preserve real URL/history semantics so page state stays reloadable/shareable without a client state graph. Push streams carry canonical versioned hemx `EffectBatch` bytes over server-owned SSE/WebSocket transport and keep `data-hemx-sse` root-scoped/same-origin by default. Preserve keyed/optional scope identity for addressable loop nodes, reconcile filtered keyed collections without clearing retained rows, prefer generated keyed-slot helpers over low-level keyed calls, and route self/row-update diagnostics toward local `data-hemx-slot`/`h-key` targets. req: canonical_authoring/002 req: canonical_authoring/014 req: modes/001 req: scope/001 req: list/001 req: list/002 req: list/003 req: list/004 req: list/005 req: list/006 req: nav/001 req: nav/002 req: nav/003 req: nav/004 req: nav/005 req: push/001 req: push/002 req: push/003 req: push/004 req: push/005 req: push/006 req: push/007 req: progressive_disclosure/004 req: page_swap/001 req: page_swap/002 req: page_swap/003 req: locality/001 req: locality/002 req: target_policy/001 req: target_policy/002
+- Typed partial swaps should stay expressed as generated target plus rendered partial plus swap kind, not selector-driven rerendering or response-side selector retargeting; HTTP, page navigation, push, and island behavior adapt around that loop, and docs should layer new primitives progressively. Navigation is an effect/page-swap concern, not a core router framework; enhanced links and GET forms preserve real URL/history semantics so page state stays reloadable/shareable without a client state graph. Push streams carry canonical versioned hemx `EffectBatch` bytes over server-owned SSE/WebSocket transport and keep `data-hemx-sse` and `data-hemx-ws` root-scoped/same-origin by default. A Cloudflare Durable Object proof keeps stable named-object authority and persisted Rust domain state, uses WebSocket hibernation for eviction recovery, and broadcasts rendered effects without storing DOM patches or effects as domain truth. Preserve keyed/optional scope identity for addressable loop nodes, reconcile filtered keyed collections without clearing retained rows, prefer generated keyed-slot helpers over low-level keyed calls, and route self/row-update diagnostics toward local `data-hemx-slot`/`h-key` targets. req: canonical_authoring/002 req: canonical_authoring/014 req: modes/001 req: scope/001 req: list/001 req: list/002 req: list/003 req: list/004 req: list/005 req: list/006 req: nav/001 req: nav/002 req: nav/003 req: nav/004 req: nav/005 req: push/001 req: push/002 req: push/003 req: push/004 req: push/005 req: push/006 req: push/007 req: push/009 req: push/010 req: push/011 req: progressive_disclosure/004 req: page_swap/001 req: page_swap/002 req: page_swap/003 req: locality/001 req: locality/002 req: target_policy/001 req: target_policy/002
 - `examples/html_examples` is the copy-paste HTML pattern gallery for htmx-style examples; keep exact htmx URL slugs visible while translating behavior to boring `.heml`, generated resources, and server-owned Rust state, not HTMX syntax, selector targeting, or user-authored browser JavaScript. Shared runtime loading and declarative `data-hemx-*` are allowed. Boost containers enhance same-origin descendants only and preserve native external/download/new-tab behavior. req: htmx_equivalents/001 req: htmx_equivalents/003 req: htmx_equivalents/005 req: examples/005 req: examples/007 req: examples/012 req: page_swap/007 req: page_swap/008
 - Use `cargo run -p hemx-xtask -- app new PATH` for the generic page/form/keyed-row/notice starter, and `cargo run -p hemx-xtask -- app new --mobile PATH` for the phone-first starter with host capabilities, recovery truth, and release-kit commands; do not treat it as a mobile framework or store-submission bot. req: ceremony/005 req: ceremony/006 req: ceremony/007
 - The public component-reuse explanation lives in `docs/recipes/reusable-partials.md`; do not grow a client component framework to explain partial composition.