docs: Deployments page moved into Ecosystem/ (#4949)

# docs: `deployments` page moved into `ecosystem/`

The `Deployments` page moved into the `Ecosystem/` group

Small fixes:
- `index` page: fixed order of items in the `Modules` list, in the `Use
Cases` list
- item `References/Installation` was lost in the `index` page (not on
the Navbar!). Restored it.
- added `|` marker in several places.

NOTE: I also thought about moving the `Additional Resources/Gallery`
page into the `Ecosystem` group but decided to leave it unchanged.
Please, advise on this.

## Who can review?

Community members can review the PR once tests pass. Tag
maintainers/contributors who might be interested:
@dev2049

docs/index.rst

@@ -67,8 +67,8 @@ For each module LangChain provides standard, extendable interfaces. LangChain al
 
    ./modules/models.rst
    ./modules/prompts.rst
-   ./modules/indexes.md
    ./modules/memory.md
+   ./modules/indexes.md
    ./modules/chains.md
    ./modules/agents.md
    ./modules/callbacks/getting_started.ipynb
@@ -115,8 +115,8 @@ Use Cases
    ./use_cases/tabular.rst
    ./use_cases/code.md
    ./use_cases/apis.md
-   ./use_cases/summarization.md
    ./use_cases/extraction.md
+   ./use_cases/summarization.md
    ./use_cases/evaluation.rst
 
 
@@ -126,7 +126,10 @@ Reference Docs
 | Full documentation on all methods, classes, installation methods, and integration setups for LangChain.
 
 
+- `LangChain Installation <./reference/installation.html>`_
+
 - `Reference Documentation <./reference.html>`_
+
 .. toctree::
    :maxdepth: 1
    :caption: Reference
@@ -141,14 +144,16 @@ Ecosystem
 ------------
 
 | LangChain integrates a lot of different LLMs, systems, and products.
-From the other side, many systems and products depend on LangChain.
+| From the other side, many systems and products depend on LangChain.
-It creates a vibrant and thriving ecosystem.
+| It creates a vibrant and thriving ecosystem.
 
 
 - `Integrations <./integrations.html>`_: Guides for how other products can be used with LangChain.
 
 - `Dependents <./dependents.html>`_: List of repositories that use LangChain.
 
+- `Deployments <./ecosystem/deployments.html>`_: A collection of instructions, code snippets, and template repositories for deploying LangChain apps.
+
 
 .. toctree::
    :maxdepth: 2
@@ -159,6 +164,7 @@ It creates a vibrant and thriving ecosystem.
 
    ./integrations.rst
    ./dependents.md
+   ./ecosystem/deployments.md
 
 
 Additional Resources
@@ -170,8 +176,6 @@ Additional Resources
 
 - `Gallery <https://github.com/kyrolabs/awesome-langchain>`_: A collection of great projects that use Langchain, compiled by the folks at `Kyrolabs <https://kyrolabs.com>`_. Useful for finding inspiration and example implementations.
 
-- `Deployments <./additional_resources/deployments.html>`_: A collection of instructions, code snippets, and template repositories for deploying LangChain apps.
-
 - `Tracing <./additional_resources/tracing.html>`_: A guide on using tracing in LangChain to visualize the execution of chains and agents.
 
 - `Model Laboratory <./additional_resources/model_laboratory.html>`_: Experimenting with different prompts, models, and chains is a big part of developing the best possible application. The ModelLaboratory makes it easy to do so.
@@ -191,7 +195,6 @@ Additional Resources
 
    LangChainHub <https://github.com/hwchase17/langchain-hub>
    Gallery <https://github.com/kyrolabs/awesome-langchain>
-   ./additional_resources/deployments.md
    ./additional_resources/tracing.md
    ./additional_resources/model_laboratory.ipynb
    Discord <https://discord.gg/6adMQxSpJS>

docs/integrations.rst

@@ -6,7 +6,7 @@ LangChain integrates with many LLMs, systems, and products.
 Integrations by Module
 --------------------------------
 
-Integrations grouped by the core LangChain module they map to:
+| Integrations grouped by the core LangChain module they map to:
 
 
 - `LLM Providers <./modules/models/llms/integrations.html>`_
@@ -23,7 +23,7 @@ Integrations grouped by the core LangChain module they map to:
 All Integrations
 -------------------------------------------
 
-A comprehensive list of LLMs, systems, and products integrated with LangChain:
+| A comprehensive list of LLMs, systems, and products integrated with LangChain:
 
 
 .. toctree::

docs/reference.rst

@@ -1,8 +1,8 @@
 API References
 ==========================
 
-All of LangChain's reference documentation, in one place.
+| Full documentation on all methods, classes, and APIs in LangChain.
-Full documentation on all methods, classes, and APIs in LangChain.
+
 
 .. toctree::
    :maxdepth: 1