feat(reader): send richer progress payload with chapter boundaries and zoom

The reader's saveProgress() now sends a more complete payload to the
backend so ProgressService has more data for enrichment and merge:

- chapter: computed from TOC boundary index instead of missing
- reading_mode: current display mode (page, chapter, percent, time-left)
- zoom_level: for fixed-layout books (renderer.zoomPercent / 100)
- current_page: real page number for fixed-layout, location.current for
  reflowable
- total_pages: section count for fixed-layout, location.total for
  reflowable

Adds computeChapterPageBoundaries(doc) for reflowable EPUBs that maps
TOC anchors to rendered page numbers, recomputes after fonts load.
Adds computeFixedLayoutChapterBoundaries() for fixed-layout books that
resolves TOC hrefs to page indices via view.resolveNavigation().

Updates reader.templ to expose isFixedLayout to Alpine init.

templates/reader.templ

@@ -154,7 +154,7 @@ templ ReaderChrome(user User, metadata ReaderMetadata, progress ReadingProgress)
 				<!-- Separator -->
 				<div class="w-px h-6 bg-gray-600 mx-1"></div>
 				<!-- Progress display -->
-				<div id="progress-display" x-text="progressText" @click="cycleProgressMode()" title="Click to change progress mode" class="text-sm min-w-[4rem] text-center cursor-pointer">
+				<div id="progress-display" x-text="progressText" @click="cycleProgressMode()" :title="progressTooltip()" class="text-sm min-w-[4rem] text-center cursor-pointer">
 					if progress.FormatGroup == "reflowable" {
 						if metadata.EstimatedPages > 0 {
 							{ fmt.Sprintf("%.0f%% · Page %d/%d", progress.Percentage, progress.CurrentPage, metadata.EstimatedPages) }

templates/reader_templ.go

@@ -181,7 +181,7 @@ func ReaderChrome(user User, metadata ReaderMetadata, progress ReadingProgress)
 		if templ_7745c5c3_Err != nil {
 			return templ_7745c5c3_Err
 		}
-		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 12, "</h1><button @click=\"toggleSettings()\" class=\"p-2 rounded-lg hover:bg-gray-700\" title=\"Settings\">⚙️</button></div></div><!-- Bottom bar --><div class=\"fixed bottom-0 left-0 right-0 bg-opacity-95 backdrop-blur border-t z-40\" style=\"background-color: var(--bg-primary);\"><div class=\"flex items-center px-2 py-2 gap-1\"><!-- Left navigation --><button @click=\"goLeft()\" class=\"p-2 rounded-lg hover:bg-gray-700\" title=\"Go Left\" aria-label=\"Go left\"><svg class=\"reader-icon\" width=\"24\" height=\"24\" aria-hidden=\"true\"><path d=\"M 15 6 L 9 12 L 15 18\"></path></svg></button><!-- Progress slider --><input id=\"progress-slider\" type=\"range\" min=\"0\" max=\"1\" step=\"any\" list=\"tick-marks\" @input=\"goToFraction($event.target.value)\" class=\"grow\"> <datalist id=\"tick-marks\"></datalist><!-- Right navigation --><button @click=\"goRight()\" class=\"p-2 rounded-lg hover:bg-gray-700\" title=\"Go Right\" aria-label=\"Go right\"><svg class=\"reader-icon\" width=\"24\" height=\"24\" aria-hidden=\"true\"><path d=\"M 9 6 L 15 12 L 9 18\"></path></svg></button><!-- Separator --><div class=\"w-px h-6 bg-gray-600 mx-1\"></div><!-- Zoom controls (fixed-layout only) --><template x-if=\"isFixedLayout\"><div class=\"flex items-center gap-1\"><!-- Zoom out --><button @click=\"zoomOut()\" class=\"p-2 rounded-lg hover:bg-gray-700\" title=\"Zoom Out\" aria-label=\"Zoom out\"><svg class=\"reader-icon\" width=\"20\" height=\"20\" aria-hidden=\"true\"><path d=\"M 5 10 L 15 10\"></path></svg></button><!-- Zoom percentage --><button @click=\"resetZoom()\" class=\"text-xs px-1 rounded-lg hover:bg-gray-700 min-w-[3rem]\" title=\"Reset Zoom\" aria-label=\"Reset zoom\"><span x-text=\"zoomPercent + '%'\">100%</span></button><!-- Zoom in --><button @click=\"zoomIn()\" class=\"p-2 rounded-lg hover:bg-gray-700\" title=\"Zoom In\" aria-label=\"Zoom in\"><svg class=\"reader-icon\" width=\"20\" height=\"20\" aria-hidden=\"true\"><path d=\"M 10 5 L 10 15 M 5 10 L 15 10\"></path></svg></button><!-- Magnifier --><button @click=\"toggleMagnifier()\" class=\"p-2 rounded-lg hover:bg-gray-700\" title=\"Magnifier\" aria-label=\"Toggle magnifier\"><svg class=\"reader-icon\" width=\"20\" height=\"20\" aria-hidden=\"true\"><circle cx=\"9\" cy=\"9\" r=\"5\"></circle> <path d=\"M 13 13 L 18 18\"></path></svg></button><!-- Pan/Select mode (PDF only) --><button x-show=\"isPDF\" @click=\"toggleInteractionMode()\" class=\"p-2 rounded-lg hover:bg-gray-700\" title=\"Pan/Select Mode\" aria-label=\"Toggle pan/select mode\"><svg class=\"reader-icon\" width=\"20\" height=\"20\" aria-hidden=\"true\"><path d=\"M 5 3 v 12 M 5 15 l -2 2 M 5 15 l 2 2 M 5 3 l 3 3\"></path></svg></button></div></template><!-- Separator --><div class=\"w-px h-6 bg-gray-600 mx-1\"></div><!-- Progress display --><div id=\"progress-display\" x-text=\"progressText\" @click=\"cycleProgressMode()\" title=\"Click to change progress mode\" class=\"text-sm min-w-[4rem] text-center cursor-pointer\">")
+		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 12, "</h1><button @click=\"toggleSettings()\" class=\"p-2 rounded-lg hover:bg-gray-700\" title=\"Settings\">⚙️</button></div></div><!-- Bottom bar --><div class=\"fixed bottom-0 left-0 right-0 bg-opacity-95 backdrop-blur border-t z-40\" style=\"background-color: var(--bg-primary);\"><div class=\"flex items-center px-2 py-2 gap-1\"><!-- Left navigation --><button @click=\"goLeft()\" class=\"p-2 rounded-lg hover:bg-gray-700\" title=\"Go Left\" aria-label=\"Go left\"><svg class=\"reader-icon\" width=\"24\" height=\"24\" aria-hidden=\"true\"><path d=\"M 15 6 L 9 12 L 15 18\"></path></svg></button><!-- Progress slider --><input id=\"progress-slider\" type=\"range\" min=\"0\" max=\"1\" step=\"any\" list=\"tick-marks\" @input=\"goToFraction($event.target.value)\" class=\"grow\"> <datalist id=\"tick-marks\"></datalist><!-- Right navigation --><button @click=\"goRight()\" class=\"p-2 rounded-lg hover:bg-gray-700\" title=\"Go Right\" aria-label=\"Go right\"><svg class=\"reader-icon\" width=\"24\" height=\"24\" aria-hidden=\"true\"><path d=\"M 9 6 L 15 12 L 9 18\"></path></svg></button><!-- Separator --><div class=\"w-px h-6 bg-gray-600 mx-1\"></div><!-- Zoom controls (fixed-layout only) --><template x-if=\"isFixedLayout\"><div class=\"flex items-center gap-1\"><!-- Zoom out --><button @click=\"zoomOut()\" class=\"p-2 rounded-lg hover:bg-gray-700\" title=\"Zoom Out\" aria-label=\"Zoom out\"><svg class=\"reader-icon\" width=\"20\" height=\"20\" aria-hidden=\"true\"><path d=\"M 5 10 L 15 10\"></path></svg></button><!-- Zoom percentage --><button @click=\"resetZoom()\" class=\"text-xs px-1 rounded-lg hover:bg-gray-700 min-w-[3rem]\" title=\"Reset Zoom\" aria-label=\"Reset zoom\"><span x-text=\"zoomPercent + '%'\">100%</span></button><!-- Zoom in --><button @click=\"zoomIn()\" class=\"p-2 rounded-lg hover:bg-gray-700\" title=\"Zoom In\" aria-label=\"Zoom in\"><svg class=\"reader-icon\" width=\"20\" height=\"20\" aria-hidden=\"true\"><path d=\"M 10 5 L 10 15 M 5 10 L 15 10\"></path></svg></button><!-- Magnifier --><button @click=\"toggleMagnifier()\" class=\"p-2 rounded-lg hover:bg-gray-700\" title=\"Magnifier\" aria-label=\"Toggle magnifier\"><svg class=\"reader-icon\" width=\"20\" height=\"20\" aria-hidden=\"true\"><circle cx=\"9\" cy=\"9\" r=\"5\"></circle> <path d=\"M 13 13 L 18 18\"></path></svg></button><!-- Pan/Select mode (PDF only) --><button x-show=\"isPDF\" @click=\"toggleInteractionMode()\" class=\"p-2 rounded-lg hover:bg-gray-700\" title=\"Pan/Select Mode\" aria-label=\"Toggle pan/select mode\"><svg class=\"reader-icon\" width=\"20\" height=\"20\" aria-hidden=\"true\"><path d=\"M 5 3 v 12 M 5 15 l -2 2 M 5 15 l 2 2 M 5 3 l 3 3\"></path></svg></button></div></template><!-- Separator --><div class=\"w-px h-6 bg-gray-600 mx-1\"></div><!-- Progress display --><div id=\"progress-display\" x-text=\"progressText\" @click=\"cycleProgressMode()\" :title=\"progressTooltip()\" class=\"text-sm min-w-[4rem] text-center cursor-pointer\">")
 		if templ_7745c5c3_Err != nil {
 			return templ_7745c5c3_Err
 		}