Remove special-casing for editable requirements (#3869)

## Summary

There are a few behavior changes in here:

- We now enforce `--require-hashes` for editables, like pip. So if you
use `--require-hashes` with an editable requirement, we'll reject it. I
could change this if it seems off.
- We now treat source tree requirements, editable or not (e.g., both `-e
./black` and `./black`) as if `--refresh` is always enabled. This
doesn't mean that we _always_ rebuild them; but if you pass
`--reinstall`, then yes, we always rebuild them. I think this is an
improvement and is close to how editables work today.

Closes #3844.

Closes #2695.

crates/uv-resolver/tests/resolver.rs

@@ -300,7 +300,6 @@ async fn black_mypy_extensions() -> Result<()> {
         Overrides::default(),
         vec![],
         None,
-        vec![],
         Exclusions::default(),
         vec![],
     );
@@ -341,7 +340,6 @@ async fn black_mypy_extensions_extra() -> Result<()> {
         Overrides::default(),
         vec![],
         None,
-        vec![],
         Exclusions::default(),
         vec![],
     );
@@ -382,7 +380,6 @@ async fn black_flake8() -> Result<()> {
         Overrides::default(),
         vec![],
         None,
-        vec![],
         Exclusions::default(),
         vec![],
     );
@@ -480,7 +477,6 @@ async fn black_respect_preference() -> Result<()> {
             Version::from_str("23.9.0")?,
         )],
         None,
-        vec![],
         Exclusions::default(),
         vec![],
     );
@@ -521,7 +517,6 @@ async fn black_ignore_preference() -> Result<()> {
             Version::from_str("23.9.2")?,
         )],
         None,
-        vec![],
         Exclusions::default(),
         vec![],
     );