docs: update headings to use sentence case instead of title case

Changed all section headings throughout the API documentation to follow
sentence case convention (only capitalizing the first word) for better
consistency and modern documentation style.

Author: zeke

api.md

@@ -6,7 +6,7 @@
 pip install replicate
 ```
 
-## Quick Start
+## Quick start
 
 ```python
 import replicate
@@ -24,7 +24,7 @@ text = claude(prompt="Write a haiku about Python")
 print(text)  # "Code flows like water..."
 ```
 
-## Client Initialization
+## Client initialization
 
 By default, the SDK uses the `REPLICATE_API_TOKEN` environment variable:
 
@@ -35,7 +35,7 @@ import replicate
 image_url = replicate.run("google/nano-banana", input={"prompt": "hello"})
 ```
 
-### Custom Client Configuration
+### Custom client configuration
 
 For advanced use cases, you can create an explicit client instance:
 
@@ -55,7 +55,7 @@ replicate = Replicate(
 image_url = replicate.run("google/nano-banana", input={"prompt": "hello"})
 ```
 
-### Asynchronous Client
+### Asynchronous client
 
 ```python
 from replicate import AsyncReplicate
@@ -74,9 +74,9 @@ async def main():
 asyncio.run(main())
 ```
 
-## High-Level Methods
+## High-level methods
 
-### use() - Create a Reusable Model Function (Recommended)
+### use() - Create a reusable model function (recommended)
 
 The most Pythonic way to interact with models. Creates a callable function for any model.
 
@@ -110,7 +110,7 @@ model = replicate.use("owner/name")  # Latest version
 model = replicate.use("5c7d5dc6dd8bf75c1acaa8565735e7986bc5b66206b55cca93cb72c9bf15ccaa")  # Version ID
 ```
 
-### run() - Run a Model Once
+### run() - Run a model once
 
 Direct method to run a model and get output. Good for one-off predictions.
 
@@ -135,7 +135,7 @@ replicate.run("owner/name", input={})  # Latest version
 replicate.run("5c7d5dc6dd8bf75c1acaa8565735e7986bc5b66206b55cca93cb72c9bf15ccaa", input={})  # Version ID
 ```
 
-### stream() - Stream Model Output
+### stream() - Stream model output
 
 For models that support streaming (like language models). Returns an iterator of output chunks.
 
@@ -155,7 +155,7 @@ async for chunk in async_replicate.stream(
     print(chunk, end="")
 ```
 
-### search() - Search Models
+### search() - Search models
 
 Find models by keyword or description.
 
@@ -167,7 +167,7 @@ for model in results:
     print(f"{model.owner}/{model.name}: {model.description}")
 ```
 
-## Core Resources
+## Core resources
 
 ### Predictions
 
@@ -236,7 +236,7 @@ model = replicate.models.create(
 replicate.models.delete(model_owner="your-username", model_name="my-model")
 ```
 
-#### Model Versions
+#### Model versions
 
 ```python
 # List model versions
@@ -261,7 +261,7 @@ replicate.models.versions.delete(
 )
 ```
 
-#### Model Predictions
+#### Model predictions
 
 Run predictions directly through a model.
 
@@ -275,7 +275,7 @@ prediction = replicate.models.predictions.create(
 # prediction.output will be an image URL when complete
 ```
 
-#### Model Examples
+#### Model examples
 
 ```python
 # Get example predictions for a model
@@ -432,9 +432,9 @@ webhook_secret = replicate.webhooks.default.secret.get()
 print(f"Webhook signing secret: {webhook_secret.key}")
 ```
 
-## File Handling
+## File handling
 
-### Input Files
+### Input files
 
 The SDK supports multiple ways to provide file inputs:
 
@@ -459,7 +459,7 @@ text = replicate.run("anthropic/claude-4-sonnet", input={
 })
 ```
 
-### Output Files
+### Output files
 
 File outputs are automatically converted to `FileOutput` objects:
 
@@ -486,7 +486,7 @@ if isinstance(image_url, FileOutput):
             f.write(chunk)
 ```
 
-## Error Handling
+## Error handling
 
 The SDK provides detailed exception types for error handling:
 
@@ -541,9 +541,9 @@ if first_page.has_next_page():
 all_models = list(replicate.models.list())
 ```
 
-## Advanced Features
+## Advanced features
 
-### Raw Response Access
+### Raw response access
 
 Access the underlying HTTP response:
 
@@ -562,7 +562,7 @@ print(f"Headers: {response.headers}")
 prediction = response.parse()
 ```
 
-### Custom HTTP Client
+### Custom HTTP client
 
 Configure a custom HTTP client for Replicate:
 
@@ -585,7 +585,7 @@ replicate = Replicate(
 )
 ```
 
-### Retries and Timeouts
+### Retries and timeouts
 
 Configure retry behavior and timeouts:
 
@@ -603,7 +603,7 @@ image_url = replicate.run(
 )
 ```
 
-### Client Copying
+### Client copying
 
 Create a new Replicate instance with modified settings:
 
@@ -616,7 +616,7 @@ new_replicate = replicate.copy(
 )
 ```
 
-## Async/Await Support
+## Async/await support
 
 All methods have async equivalents when using `AsyncReplicate`:
 
@@ -656,14 +656,14 @@ async def main():
 asyncio.run(main())
 ```
 
-## Environment Variables
+## Environment variables
 
 The SDK respects these environment variables:
 
 - `REPLICATE_API_TOKEN` - API authentication token
 - `REPLICATE_BASE_URL` - Override the API base URL (default: `https://api.replicate.com/v1`)
 
-## Type Hints
+## Type hints
 
 The SDK is fully typed with comprehensive type hints:
 
@@ -680,9 +680,9 @@ status: PredictionStatus = prediction.status
 page: SyncCursorURLPage[Prediction] = replicate.predictions.list()
 ```
 
-## Common Patterns
+## Common patterns
 
-### Wait for Completion with Polling
+### Wait for completion with polling
 
 ```python
 import time
@@ -702,7 +702,7 @@ prediction = replicate.predictions.create(model="model:version", input={})
 result = wait_for_prediction(replicate, prediction.id)
 ```
 
-### Batch Processing
+### Batch processing
 
 ```python
 import asyncio
@@ -723,7 +723,7 @@ prompts = ["prompt 1", "prompt 2", "prompt 3"]
 results = asyncio.run(batch_process(prompts))
 ```
 
-### Webhook Handling
+### Webhook handling
 
 ```python
 from flask import Flask, request
@@ -761,7 +761,7 @@ def webhook():
     return "OK", 200
 ```
 
-## Migration Guide
+## Migration guide
 
 ### From v0.x to v1.0+
 
@@ -798,7 +798,7 @@ model = replicate.models.get(
 )
 ```
 
-### Using Legacy Authentication
+### Using legacy authentication
 
 For compatibility with older code: