Tree: Unify sampler parameters and add override support

Unify API sampler params into a superclass which should make them
easier to manage and inherit generic functions from.

Not all frontends expose all sampling parameters due to connections
with OAI (that handles sampling themselves with the exception of
a few sliders).

Add the ability for the user to customize fallback parameters from
server-side.

In addition, parameters can be forced to a certain value server-side
in case the repo automatically sets other sampler values in the
background that the user doesn't want.

Signed-off-by: kingbri <bdashore3@proton.me>

sampler_overrides/sample_preset.yml

@@ -0,0 +1,94 @@
+# Sample YAML file for override presets.
+# Each block corresponds to a sampler fallback override. Remove ones that you don't need.
+# "force" always overrides the sampler to the specified value.
+# For example, a top-p override of 1.5 with force = true will make every API request have a top_p value of 1.5
+
+# You can use https://www.yamllint.com/ if you want to check your YAML formatting.
+
+# TODO: Improve documentation for each field
+
+# MARK: Misc generation parameters
+max_tokens:
+  override: 150
+  force: false
+stop:
+  override: []
+  force: false
+token_healing:
+  override: false
+  force: false
+
+# MARK: Temperature
+temperature:
+  override: 1.0
+  force: false
+temperature_last:
+  override: false
+  force: false
+
+# MARK: Alphabet soup
+top_k:
+  override: 0
+  force: false
+top_p:
+  override: 1.0
+  force: false
+top_a:
+  override: 0.0
+  force: false
+min_p:
+  override: 0.0
+  force: false
+tfs:
+  override: 0.0
+  force: false
+typical:
+  override: 1.0
+  force: false
+
+# MARK: Penalty settings
+frequency_penalty:
+  override: 0.0
+  force: false
+presence_penalty:
+  override: 0.0
+  force: false
+repetition_penalty:
+  override: 1.0
+  force: false
+repetition_decay:
+  override: 0
+  force: false
+penalty_range:
+  override: -1
+  force: false
+
+# MARK: Mirostat
+mirostat_mode:
+  override: 0
+  force: false
+mirostat_tau:
+  override: 1.5
+  force: false
+mirostat_eta:
+  override: 0.3
+  force: false
+
+# MARK: Token options
+add_bos_token:
+  override: true
+  force: false
+ban_eos_token:
+  override: false
+  force: false
+logit_bias:
+  override:
+  force: false
+
+# MARK: CFG scale
+cfg_scale:
+  override: 1.0
+  force: false
+negative_prompt:
+  override:
+  force: false