fix: proxy/attempts truthiness bugs, stale text() cache, preview cookie order (v0.1.9)

_get_proxy() and request() checked proxies/proxy with truthiness instead of
is None, so a per-call proxies={} silently fell back to session proxies, and a
native proxy= kwarg was clobbered by resolved session proxies (unmasking the
caller's real IP) instead of raising on conflicting sources. Response.text()
cached the first decode regardless of a later explicit encoding= argument.
preview() computed the Cookie header from the pre-rewrite url instead of the
rewritten one actually used by request(). request_with_retries(attempts=0)
became DEFAULT_ATTEMPTS via truthiness instead of flooring to 1.

Also compresses docstrings/comments across the module (no behavior change).

Signed-off-by: disqualifier <dev@disqualifier.me>

README.md

@@ -11,18 +11,18 @@ and swap the HTTP client while inheriting everything else.
 `requirements.txt`:
 
 ```
-aioweb @ git+ssh://git@git.rethinkstudios.io/rethink-public/aioweb.git@v0.1.8
+aioweb @ git+ssh://git@git.rethinkstudios.io/rethink-public/aioweb.git@v0.1.9
 ```
 
 Direct:
 
 ```bash
-pip install "aioweb @ git+ssh://git@git.rethinkstudios.io/rethink-public/aioweb.git@v0.1.8"
+pip install "aioweb @ git+ssh://git@git.rethinkstudios.io/rethink-public/aioweb.git@v0.1.9"
 ```
 
 Requires `aiohttp` and `yarl` (pulled transitively).
 
-Drop the `@v0.1.8` suffix from the line above to install the latest unpinned.
+Drop the `@v0.1.9` suffix from the line above to install the latest unpinned.
 
 ## Usage
 
@@ -144,6 +144,24 @@ Two changes can't be shimmed without re-introducing the bugs they fix:
 
 ## Changelog
 
+### v0.1.9
+
+- **`_get_proxy()`/`request()` proxy resolution now checks `is None`, not
+  truthiness.** A per-call `proxies={}` previously fell back to the session's
+  configured proxies instead of disabling them for that call. `request()` also no
+  longer clobbers a native `proxy=` kwarg with the resolved session/`proxies=`
+  value (a real IP-unmasking leak) — passing both now raises `ValueError` instead
+  of silently picking one.
+- **`Response.text(encoding=...)` no longer returns a stale cached decode.** A
+  second call with an explicit `encoding=` previously still returned the first
+  (possibly differently-encoded) cached decode; an explicit encoding now bypasses
+  the cache.
+- **`preview()` now rewrites the url before resolving cookies**, matching what
+  `request()` actually sends — previously cookies were resolved against the
+  pre-rewrite host, which could miss or misattribute host-bound cookies.
+- **`request_with_retries(attempts=0)` now floors to 1 attempt**, not silently
+  `DEFAULT_ATTEMPTS` (3). `attempts` is checked with `is None`, not truthiness.
+
 ### v0.1.8
 
 - **`request()` no longer flattens `aiohttp.ClientError` subtypes.** Every failure