[red-knot] Infer subscript expression types for bytes literals (#13901)

## Summary

Infer subscript expression types for bytes literals:
```py
b = b"\x00abc\xff"

reveal_type(b[0])  # revealed: Literal[b"\x00"]
reveal_type(b[1])  # revealed: Literal[b"a"]
reveal_type(b[-1])  # revealed: Literal[b"\xff"]
reveal_type(b[-2])  # revealed: Literal[b"c"]

reveal_type(b[False])  # revealed: Literal[b"\x00"]
reveal_type(b[True])  # revealed: Literal[b"a"]
```


part of #13689
(https://github.com/astral-sh/ruff/issues/13689#issuecomment-2404285064)

## Test Plan

- New Markdown-based tests (see `mdtest/subscript/bytes.md`)
- Added missing test for `string_literal[bool_literal]`

crates/red_knot_python_semantic/resources/mdtest/subscript/bytes.md

@@ -3,8 +3,33 @@
 ## Simple
 
 ```py
-reveal_type(b"red" b"knot")  # revealed: Literal[b"redknot"]
-reveal_type(b"hello")  # revealed: Literal[b"hello"]
-reveal_type(b"world" + b"!")  # revealed: Literal[b"world!"]
-reveal_type(b"\xff\x00")  # revealed: Literal[b"\xff\x00"]
+b = b"\x00abc\xff"
+
+reveal_type(b[0])  # revealed: Literal[b"\x00"]
+reveal_type(b[1])  # revealed: Literal[b"a"]
+reveal_type(b[4])  # revealed: Literal[b"\xff"]
+
+reveal_type(b[-1])  # revealed: Literal[b"\xff"]
+reveal_type(b[-2])  # revealed: Literal[b"c"]
+reveal_type(b[-5])  # revealed: Literal[b"\x00"]
+
+reveal_type(b[False])  # revealed: Literal[b"\x00"]
+reveal_type(b[True])  # revealed: Literal[b"a"]
+
+x = b[5]  # error: [index-out-of-bounds] "Index 5 is out of bounds for bytes literal `Literal[b"\x00abc\xff"]` with length 5"
+reveal_type(x)  # revealed: Unknown
+
+y = b[-6]  # error: [index-out-of-bounds] "Index -6 is out of bounds for bytes literal `Literal[b"\x00abc\xff"]` with length 5"
+reveal_type(y)  # revealed: Unknown
+```
+
+## Function return
+
+```py
+def int_instance() -> int: ...
+
+
+a = b"abcde"[int_instance()]
+# TODO: Support overloads... Should be `bytes`
+reveal_type(a)  # revealed: @Todo
 ```