Phase 6: Replace render_template() with s-expression rendering in all GET routes

Migrate ~52 GET route handlers across all 7 services from Jinja
render_template() to s-expression component rendering. Each service
gets a sexp_components.py with page/oob/cards render functions.

- Add per-service sexp_components.py (account, blog, cart, events,
  federation, market, orders) with full page, OOB, and pagination
  card rendering
- Add shared/sexp/helpers.py with call_url, root_header_html,
  full_page, oob_page utilities
- Update all GET routes to use get_template_context() + render fns
- Fix get_template_context() to inject Jinja globals (URL helpers)
- Add qs_filter to base_context for sexp filter URL building
- Mount sexp_components.py in docker-compose.dev.yml for all services
- Import sexp_components in app.py for Hypercorn --reload watching
- Fix route_prefix import (shared.utils not shared.infrastructure.urls)
- Fix federation choose-username missing actor in context
- Fix market page_markets missing post in context

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

shared/sexp/helpers.py

@@ -0,0 +1,108 @@
+"""
+Shared helper functions for s-expression page rendering.
+
+These are used by per-service sexp_components.py files to build common
+page elements (headers, search, etc.) from template context.
+"""
+from __future__ import annotations
+
+from typing import Any
+
+from .jinja_bridge import sexp
+from .page import HAMBURGER_HTML, SEARCH_HEADERS_MOBILE, SEARCH_HEADERS_DESKTOP
+
+
+def call_url(ctx: dict, key: str, path: str = "/") -> str:
+    """Call a URL helper from context (e.g., blog_url, account_url)."""
+    fn = ctx.get(key)
+    if callable(fn):
+        return fn(path)
+    return str(fn or "") + path
+
+
+def get_asset_url(ctx: dict) -> str:
+    """Extract the asset URL base from context."""
+    au = ctx.get("asset_url")
+    if callable(au):
+        result = au("")
+        return result.rsplit("/", 1)[0] if "/" in result else result
+    return au or ""
+
+
+def root_header_html(ctx: dict, *, oob: bool = False) -> str:
+    """Build the root header row HTML."""
+    return sexp(
+        '(~header-row :cart-mini-html cmi :blog-url bu :site-title st'
+        ' :nav-tree-html nth :auth-menu-html amh :nav-panel-html nph'
+        ' :hamburger-html hh :oob oob)',
+        cmi=ctx.get("cart_mini_html", ""),
+        bu=call_url(ctx, "blog_url", ""),
+        st=ctx.get("base_title", ""),
+        nth=ctx.get("nav_tree_html", ""),
+        amh=ctx.get("auth_menu_html", ""),
+        nph=ctx.get("nav_panel_html", ""),
+        hh=HAMBURGER_HTML,
+        oob=oob,
+    )
+
+
+def search_mobile_html(ctx: dict) -> str:
+    """Build mobile search input HTML."""
+    return sexp(
+        '(~search-mobile :current-local-href clh :search s :search-count sc'
+        ' :hx-select hs :search-headers-mobile shm)',
+        clh=ctx.get("current_local_href", "/"),
+        s=ctx.get("search", ""),
+        sc=ctx.get("search_count", ""),
+        hs=ctx.get("hx_select", "#main-panel"),
+        shm=SEARCH_HEADERS_MOBILE,
+    )
+
+
+def search_desktop_html(ctx: dict) -> str:
+    """Build desktop search input HTML."""
+    return sexp(
+        '(~search-desktop :current-local-href clh :search s :search-count sc'
+        ' :hx-select hs :search-headers-desktop shd)',
+        clh=ctx.get("current_local_href", "/"),
+        s=ctx.get("search", ""),
+        sc=ctx.get("search_count", ""),
+        hs=ctx.get("hx_select", "#main-panel"),
+        shd=SEARCH_HEADERS_DESKTOP,
+    )
+
+
+def full_page(ctx: dict, *, header_rows_html: str,
+              filter_html: str = "", aside_html: str = "",
+              content_html: str = "", menu_html: str = "",
+              body_end_html: str = "", meta_html: str = "") -> str:
+    """Render a full app page with the standard layout."""
+    return sexp(
+        '(~app-layout :title t :asset-url au :meta-html mh'
+        ' :header-rows-html hrh :menu-html muh :filter-html fh'
+        ' :aside-html ash :content-html ch :body-end-html beh)',
+        t=ctx.get("base_title", "Rose Ash"),
+        au=get_asset_url(ctx),
+        mh=meta_html,
+        hrh=header_rows_html,
+        muh=menu_html,
+        fh=filter_html,
+        ash=aside_html,
+        ch=content_html,
+        beh=body_end_html,
+    )
+
+
+def oob_page(ctx: dict, *, oobs_html: str = "",
+             filter_html: str = "", aside_html: str = "",
+             content_html: str = "", menu_html: str = "") -> str:
+    """Render an OOB response with standard swap targets."""
+    return sexp(
+        '(~oob-response :oobs-html oh :filter-html fh :aside-html ash'
+        ' :menu-html mh :content-html ch)',
+        oh=oobs_html,
+        fh=filter_html,
+        ash=aside_html,
+        mh=menu_html,
+        ch=content_html,
+    )