[ai] Make a more complex task workflow.

AGENTS.md

@@ -186,7 +186,15 @@ api().request(MTPnamespace_MethodName(
 **Key points:**
 - Always refer to `api.tl` for method signatures and return types
 - Use generated `MTP...` types for parameters (`MTP_int`, `MTP_string`, etc.)
-- For multiple constructors, use `.match()` or check `.type()` then `.c_constructor()`
+- For multiple constructors, use `.match()` or check `.type()` against `mtpc_` constants then call `.c_constructorName()`:
+  ```cpp
+  // Using match:
+  result.match([&](const MTPDuser &data) { ... }, [&](const MTPDuserEmpty &data) { ... });
+  // Or explicit type check:
+  if (result.type() == mtpc_user) {
+      const auto &data = result.c_user(); // asserts on type mismatch
+  }
+  ```
 - For single constructors, use `.data()` shortcut
 - Include `.handleFloodErrors()` before `.send()` in rare cases where you want special case flood error handling
 
@@ -218,7 +226,8 @@ primaryButton: MyButtonStyle(defaultButton) {
 ```
 
 **Built-in types:**
-- `int` - Integer numbers
+- `int` - Integer numbers (e.g., `maxLines: 3;`)
+- `bool` - Boolean values (e.g., `useShadow: true;`)
 - `pixels` - Pixel values with `px` suffix (e.g., `10px`)
 - `color` - Named colors from `ui/colors.palette`
 - `icon` - Inline icon definition: `icon{{ "path/stem", color }}`
@@ -229,6 +238,22 @@ primaryButton: MyButtonStyle(defaultButton) {
 - `font` - Font: `font(14px semibold)`
 - `double` - Floating point
 
+**Multi-part icons** (layers drawn bottom-up):
+```style
+myComplexIcon: icon{
+  { "gui/icons/background", iconBgColor },
+  { "gui/icons/foreground", iconFgColor }
+};
+```
+
+**Borders** are typically separate fields, not a single property:
+```style
+chatInput {
+  border: 1px;                       // width
+  borderFg: defaultInputFieldBorder; // color
+}
+```
+
 **Never hardcode sizes in code:**
 
 The app supports different interface scale options. Style `px` values are automatically scaled at runtime, but raw integer constants in code are not. Never use hardcoded numbers for margins, paddings, spacing, sizes, coordinates, or any other dimensional values. Always define them in `.style` files and reference via `st::`.
@@ -311,6 +336,20 @@ auto filesTextProducer = tr::lng_files_selected(
 - Placeholders use `lt_tag_name, value` pattern
 - For `{count}`: immediate uses `int`, reactive uses `rpl::producer<float64>` with `| tr::to_count()`
 - Move producers with `std::move` when passing to placeholders
+- Rich text projectors — pass as the last argument to produce `TextWithEntities` instead of `QString`. These are smart objects with multiple `operator()` overloads:
+  - `tr::marked` — basic projection, converts `QString` to `TextWithEntities`
+  - `tr::rich` — interprets `**bold**`/`__italic__` markup in the string
+  - `tr::bold`, `tr::italic`, `tr::underline` — wrap text in that formatting
+  - `tr::link` — wrap as a clickable link
+  - `tr::url(u"https://..."_q)` — returns a projection that converts text to a link pointing to the given URL; can be passed to `rpl::map` or directly to a `tr::lng_...` call
+  ```cpp
+  auto title = tr::lng_export_progress_title(tr::now, tr::bold);
+  auto text = tr::lng_proxy_incorrect_secret(tr::now, tr::rich);
+  auto linked = tr::lng_settings_birthday_contacts(
+      lt_link,
+      tr::lng_settings_birthday_contacts_link(tr::url(link)),
+      tr::marked);
+  ```
 
 ## RPL (Reactive Programming Library)
 
@@ -370,9 +409,16 @@ std::move(merged) | rpl::on_next([=](QString &&value) {
 }, lifetime);
 ```
 
+**Other pipeline starters** — besides `rpl::on_next`, there are:
+- `rpl::on_error([=](Error &&e) { ... }, lifetime)` — handle errors
+- `rpl::on_done([=] { ... }, lifetime)` — handle stream completion
+- `rpl::on_next_error_done(nextCb, errorCb, doneCb, lifetime)` — handle all three
+
+The `Error` template parameter defaults to `rpl::no_error`: `rpl::producer<Type, Error = no_error>`.
+
 **Key points:**
 - Explicitly `std::move` producers when starting pipelines
 - Pass `rpl::lifetime` to `on_...` methods or store returned lifetime
 - Use `rpl::duplicate(producer)` to reuse a producer multiple times
-- Combined producers automatically unpack tuples in lambdas
+- Combined producers automatically unpack tuples in lambdas (works with `rpl::map`, `rpl::filter`, and `rpl::on_next`)