Add user context notes field to timeline tool

Adds an optional textarea below the main text input where users can provide
clarifications to guide the LLM — e.g. year anchors, actor aliases, or focus
instructions. Notes are injected into the prompt as a clearly delimited block
and translated across all four UI languages (en/no/uk/pl).

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

timeline.php

@@ -72,6 +72,12 @@ require_once __DIR__ . '/includes/layout.php';
                     <label class="input-label" for="toolInput" id="inputLabel" data-i18n="timelineInputLabel">Pasted text</label>
                     <textarea id="toolInput" name="toolInput" rows="10" required data-i18n-placeholder="timelineInputPlaceholder" placeholder="Paste case notes, court decisions, or correspondence containing dates and events."></textarea>
 
+                    <div id="timelineNotesSection">
+                        <label class="input-label" for="timelineNotes" data-i18n="timelineNotesLabel">Context notes <small class="control-hint">(optional)</small></label>
+                        <textarea id="timelineNotes" name="timelineNotes" rows="3" data-i18n-placeholder="timelineNotesPlaceholder" placeholder="Add any clarifications to guide the AI — e.g. &quot;All dates are 2024&quot;, &quot;Focus on the mother's actions&quot;, &quot;D refers to the defendant throughout&quot;."></textarea>
+                        <p class="upload-hint" data-i18n="timelineNotesHint">These notes are included in the prompt to help the model interpret ambiguous dates, actors, or abbreviations. Not stored.</p>
+                    </div>
+
                     <div class="form-footer">
                         <p id="toolStatus" class="form-status" role="status" aria-live="polite"></p>
                         <button id="runButton" type="submit" data-i18n="timelineRun">Run</button>