feat(assistant): search the web too, and choose what goes along

The assistant's field now has a switch at its start: a question goes to
Claude or into a web search, and the field remembers which. A web search
opens the chosen engine's results: on Android the device's own web
search by default (ACTION_WEB_SEARCH, answered by its default browser or
search app; Brave Search where nothing answers), elsewhere Brave Search
by default; Settings › Assistant › Search engine offers Ecosia,
DuckDuckGo, Startpage, Qwant, Google, Bing, or one's own address with
%s where the question goes.

Above the field, chips offer what the question is about: a card's
front, back, each hint and its explanation, the studyset's name and
description. None is chosen, so only what the person picks goes along,
each part cut at 600 characters; Claude gets the question and a compact
line per chosen part, a web search the question and the chosen text,
never the studyset's name. A chosen chip alone is enough to send. The
old sentences around every question (where it was asked, the connector)
are gone: they cost tokens for nothing unless the studyset is chosen.

On a studyset's screen the button now stands above the bottom bar, as in
the Library: unfolded inside the bar, its chips lay outside the bar's
bounds, where taps don't land.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MMm7usAo6q9ZZRoPkWjoxi
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

halkyon_learn_flutter/lib/l10n/app_en.arb

@@ -1789,22 +1789,16 @@
   "kanjiExampleWords": "Words with it",
 
   "settingsAssistant": "Assistant",
-  "settingsAskClaude": "Ask Claude",
-  "settingsAskClaudeSubtitle": "Off unless you turn it on. Adds a field on Home and a button in the Library, on a studyset and while studying. A question opens in Claude with what it is about, and you send it there; nothing is sent from here.",
+  "settingsAskClaude": "Ask Claude or search the web",
+  "settingsAskClaudeSubtitle": "Off unless you turn it on. Adds a field on Home and a button in the Library, on a studyset and while studying. A question opens in Claude or as a web search, with only the context you choose; nothing is sent from here.",
   "assistantHint": "Ask Claude…",
   "assistantHintStudyset": "Ask Claude about {title}…",
   "@assistantHintStudyset": {"placeholders": {"title": {"type": "String"}}},
   "assistantHintCard": "Ask Claude about this card…",
   "assistantSend": "Ask in Claude",
-  "assistantOpen": "Ask Claude",
+  "assistantOpen": "Ask or search",
   "assistantClose": "Close",
   "assistantOpenFailed": "Claude couldn't be opened.",
-  "assistantPromptLearning": "{question}\n\n(Asked from Halkyon Learn, where I learn with studysets on {instance}. If you have the Halkyon Learn connector, you can read them there.)",
-  "@assistantPromptLearning": {"description": "What the app hands to Claude: the person's question, then where it was asked. Written as the person, to Claude.", "placeholders": {"question": {"type": "String"}, "instance": {"type": "String"}}},
-  "assistantPromptStudyset": "{question}\n\n(About my studyset “{title}” in Halkyon Learn on {instance}. If you have the Halkyon Learn connector, you can read it there.)",
-  "@assistantPromptStudyset": {"placeholders": {"question": {"type": "String"}, "title": {"type": "String"}, "instance": {"type": "String"}}},
-  "assistantPromptCard": "{question}\n\n(About a flashcard I am studying, in my studyset “{title}” in Halkyon Learn on {instance}.\nFront: {front}\nBack: {back})",
-  "@assistantPromptCard": {"placeholders": {"question": {"type": "String"}, "title": {"type": "String"}, "front": {"type": "String"}, "back": {"type": "String"}, "instance": {"type": "String"}}},
 
   "assistantConnectTitle": "Connect Claude",
   "assistantConnectSubtitle": "Let Claude read your studysets",
@@ -1830,5 +1824,34 @@
   "assistantDisconnectMessage": "It can't read your studysets any more. You can connect it again with a new code.",
   "assistantNotOffered": "This instance doesn't offer a connector yet. Questions still open in Claude with what they are about.",
   "assistantUnreachable": "The instance can't be reached. Try again once you are online.",
-  "assistantRetry": "Try again"
+  "assistantRetry": "Try again",
+
+  "assistantLineFront": "Front: {text}",
+  "@assistantLineFront": {"description": "A line of context handed to Claude after the question.", "placeholders": {"text": {"type": "String"}}},
+  "assistantLineBack": "Back: {text}",
+  "@assistantLineBack": {"placeholders": {"text": {"type": "String"}}},
+  "assistantLineHint": "Hint {number}: {text}",
+  "@assistantLineHint": {"placeholders": {"number": {"type": "int"}, "text": {"type": "String"}}},
+  "assistantLineExplanation": "Explanation: {text}",
+  "@assistantLineExplanation": {"placeholders": {"text": {"type": "String"}}},
+  "assistantLineStudyset": "Studyset: “{title}” in Halkyon Learn on {instance}",
+  "@assistantLineStudyset": {"placeholders": {"title": {"type": "String"}, "instance": {"type": "String"}}},
+  "assistantLineDescription": "Description: {text}",
+  "@assistantLineDescription": {"placeholders": {"text": {"type": "String"}}},
+  "assistantChipStudyset": "Studyset: {title}",
+  "@assistantChipStudyset": {"placeholders": {"title": {"type": "String"}}},
+  "assistantContextLabel": "Send along",
+  "assistantTargetClaude": "Claude",
+  "assistantTargetWeb": "Web",
+  "assistantSwitchToWeb": "Search the web instead",
+  "assistantSwitchToClaude": "Ask Claude instead",
+  "assistantHintWeb": "Search the web…",
+  "assistantSendWeb": "Search",
+  "assistantSearchFailed": "The search couldn't be opened.",
+  "settingsSearchEngine": "Search engine",
+  "searchEngineDevice": "The device's search",
+  "searchEngineCustom": "Your own address",
+  "searchEngineCustomHint": "https://example.org/search?q=%s",
+  "searchEngineCustomInvalid": "An http or https address with %s where the question goes.",
+  "searchEngineCustomSave": "Use"
 }