feat: add source hyperlinks + remove thin from-source.md

Every source reference now links to elixir-lang/elixir at commit f4e1b34.
122 hyperlinks across 11 topic files. Added PATTERN_COMPLETE sentinels.
Removed from-source.md (326 lines, shallow) — covered by existing files.

patterns/modules.md

@@ -214,7 +214,7 @@ end
 
 ## 3. `@moduledoc false` for Internal Modules
 
-**Source:** `lib/phoenix/router/route.ex:5-7`
+**Source:** [lib/phoenix/router/route.ex#L5](https://github.com/elixir-lang/elixir/blob/f4e1b34617ef92052b65781f18eae5b88a490098/lib/phoenix/router/route.ex#L5)
 
 ```elixir
 # This module defines the Route struct that is used
@@ -289,7 +289,7 @@ end
 
 ## 4. Struct Definition Conventions
 
-**Source:** `lib/elixir/lib/task.ex:279-296`
+**Source:** [lib/elixir/lib/task.ex#L279](https://github.com/elixir-lang/elixir/blob/f4e1b34617ef92052b65781f18eae5b88a490098/lib/elixir/lib/task.ex#L279)
 
 ```elixir
 @enforce_keys [:mfa, :owner, :pid, :ref]
@@ -303,7 +303,7 @@ defstruct @enforce_keys
       }
 ```
 
-**Source:** `lib/phoenix/router/route.ex:30-46`
+**Source:** [lib/phoenix/router/route.ex#L30](https://github.com/elixir-lang/elixir/blob/f4e1b34617ef92052b65781f18eae5b88a490098/lib/phoenix/router/route.ex#L30)
 
 ```elixir
 defstruct [
@@ -389,14 +389,14 @@ end
 
 ## 5. Selective Imports in `__using__`
 
-**Source:** `lib/phoenix/channel.ex:463-464`
+**Source:** [lib/phoenix/channel.ex#L463](https://github.com/elixir-lang/elixir/blob/f4e1b34617ef92052b65781f18eae5b88a490098/lib/phoenix/channel.ex#L463)
 
 ```elixir
 import unquote(__MODULE__)
 import Phoenix.Socket, only: [assign: 3, assign: 2]
 ```
 
-**Source:** `lib/phoenix/router.ex:271-275`
+**Source:** [lib/phoenix/router.ex#L271](https://github.com/elixir-lang/elixir/blob/f4e1b34617ef92052b65781f18eae5b88a490098/lib/phoenix/router.ex#L271)
 
 ```elixir
 import Phoenix.Router
@@ -471,7 +471,7 @@ end
 
 ## 6. Alias at Module Scope for Readability
 
-**Source:** `lib/phoenix/router.ex:268`
+**Source:** [lib/phoenix/router.ex#L268](https://github.com/elixir-lang/elixir/blob/f4e1b34617ef92052b65781f18eae5b88a490098/lib/phoenix/router.ex#L268)
 
 ```elixir
 alias Phoenix.Router.{Resource, Scope, Route, Helpers}
@@ -538,7 +538,7 @@ end
 
 ## 7. Boolean-Suffixed Fields in Structs
 
-**Source:** `lib/phoenix/router/route.ex:43-44`
+**Source:** [lib/phoenix/router/route.ex#L43](https://github.com/elixir-lang/elixir/blob/f4e1b34617ef92052b65781f18eae5b88a490098/lib/phoenix/router/route.ex#L43)
 
 ```elixir
 :trailing_slash?,
@@ -589,3 +589,5 @@ defstruct [:user, :admin?, :count]
 ```
 
 **Why:** The `?` suffix should only mark genuine booleans. Using it on non-boolean fields creates confusion about the field's type and breaks the convention's usefulness as a type signal.
+
+<!-- PATTERN_COMPLETE -->