[random] introduce template-based NonCrypto random APIs (#13142)

This commit introduces a new set of template-based APIs for
non-cryptographic random number generation in the `Random::NonCrypto`
namespace. These new methods provide a cleaner, type-safe, and more
robust interface compared to the previous methods.

Key additions:
- `Generate<UintType>()`: Returns a random value of the given
  unsigned integer type (`uint8_t`, `uint16_t`, or `uint32_t`).
- `GenerateUpToExcluding<UintType>(aMax)`: Returns a random value in
  the range `[0, aMax)`.
- `GenerateFromMinUpToExcluding<UintType>(aMin, aMax)`: Returns a
  random value in the range `[aMin, aMax)`.
- `GenerateInClosedRange<UintType>(aMin, aMax)`: Returns a random
  value in the closed range `[aMin, aMax]`.

The introduction of `GenerateInClosedRange` is an improvement as it
safely handles ranges up to the maximum value of the integer type
(e.g., `0xffff`) without the risk of overflow.

All call sites across the OpenThread core stack and tests have been
updated to adopt these new APIs. The public `otRandomNonCrypto`
functions are also updated to leverage the new internal methods.

Doxygen documentation is added for all new template methods,
detailing their behavior, including edge cases where the upper bound
is smaller than or equal to the lower bound.

tests/unit/test_spinel_buffer.cpp

@@ -887,7 +887,7 @@ uint32_t GetRandom(uint32_t max)
     }
     else
     {
-        value = Random::NonCrypto::GetUint32();
+        value = Random::NonCrypto::Generate<uint32_t>();
     }
 
     return value % max;