Implement postfix adjustment hints

I'd say "First stab at implementing..." but I've been working on this
for a month already lol

crates/rust-analyzer/src/config.rs

@@ -333,6 +333,8 @@ config_data! {
         inlayHints_expressionAdjustmentHints_enable: AdjustmentHintsDef = "\"never\"",
         /// Whether to hide inlay hints for type adjustments outside of `unsafe` blocks.
         inlayHints_expressionAdjustmentHints_hideOutsideUnsafe: bool = "false",
+        /// Whether to show inlay hints for type adjustments as postfix ops (`.*` instead of `*`, etc).
+        inlayHints_expressionAdjustmentHints_postfix: bool = "false",
         /// Whether to show inlay type hints for elided lifetimes in function signatures.
         inlayHints_lifetimeElisionHints_enable: LifetimeElisionDef = "\"never\"",
         /// Whether to prefer using parameter names as the name for elided lifetime hints if possible.
@@ -1252,6 +1254,7 @@ impl Config {
                 },
                 AdjustmentHintsDef::Reborrow => ide::AdjustmentHints::ReborrowOnly,
             },
+            adjustment_hints_postfix: self.data.inlayHints_expressionAdjustmentHints_postfix,
             adjustment_hints_hide_outside_unsafe: self
                 .data
                 .inlayHints_expressionAdjustmentHints_hideOutsideUnsafe,

crates/rust-analyzer/src/to_proto.rs

@@ -452,6 +452,7 @@ pub(crate) fn inlay_hint(
             | InlayKind::ChainingHint
             | InlayKind::GenericParamListHint
             | InlayKind::ClosingParenthesis
+            | InlayKind::AdjustmentHintPostfix
             | InlayKind::LifetimeHint
             | InlayKind::ClosingBraceHint => position(line_index, inlay_hint.range.end()),
         },
@@ -465,6 +466,7 @@ pub(crate) fn inlay_hint(
             | InlayKind::ClosureReturnTypeHint
             | InlayKind::GenericParamListHint
             | InlayKind::AdjustmentHint
+            | InlayKind::AdjustmentHintPostfix
             | InlayKind::LifetimeHint
             | InlayKind::ParameterHint => false,
         }),
@@ -475,6 +477,7 @@ pub(crate) fn inlay_hint(
             | InlayKind::ClosureReturnTypeHint
             | InlayKind::GenericParamListHint
             | InlayKind::AdjustmentHint
+            | InlayKind::AdjustmentHintPostfix
             | InlayKind::TypeHint
             | InlayKind::DiscriminantHint
             | InlayKind::ClosingBraceHint => false,
@@ -493,6 +496,7 @@ pub(crate) fn inlay_hint(
             | InlayKind::GenericParamListHint
             | InlayKind::LifetimeHint
             | InlayKind::AdjustmentHint
+            | InlayKind::AdjustmentHintPostfix
             | InlayKind::ClosingBraceHint => None,
         },
         text_edits: None,